The correct option is:(d) A is false, but R is true.

Explanation:

In our houses, the frequency of alternating voltage supplied is 50 Hz, i.e. 50 times per second. In America, frequency of A.C. line is 60 Hz.

The correct option is: (c) Both 1 and 2

Explanation:

The intersected area of magenta and yellow-coloured circles will have red colour. The intersected area of cyan and magenta coloured circles will have blue colour.

Magenta = Red + Blue 

Cyan = Blue + Green

Babies will develop control of their head, neck and upper body during the first few months of life. By month six, babies have increased flexibility and may be able to roll over, move around on their tummy and sit up if placed in a sitting position.

The temperature measurement through the platinum resistance thermometer is easier as compared to the gas thermometer. The meter gives a precise reading of temperature. The thermometer has a wide range from 200 to 1200° Celsius.

X(55-50) = 40(95-55)

 5X =40 x 40

  X =1600/5

   X =320g 

The weight of ruler is 320g.

Mars Science Fair Project Ideas.

1. Build a scale model of our solar system. Where does Mars fit in the grand scheme of all the other planets
2. Explain the forces at work when Mars orbits the sun.
3. Study pictures of Mars. What new discoveries did we learn from pictures the rovers sent back versus satellite photos NASA captured before? How does the Martian landscape differ from Earth? Are there places on Earth that resemble Mars?
4. What are the features of Mars Could they support some kind of life or not?
5. Why is Mars red? Is Mars really red on the surface or is it an optical illusion? What minerals are on Mars that cause it to appear red? Relate your discoveries to things we can relate to on Earth and show pictures.
6. What have we learned in the various missions to Mars? What were the most significant discoveries? What questions did each successful mission answer and did a later mission prove these wrong?
7. What does NASA have planned for future Mars missions? Will they be able to build a Mars colony? If so, what will it look like and how are they preparing for it?
8. How long does it take to travel to Mars? When astronauts are sent to Mars, what will the trip be like? Are photographs sent back from Mars in real-time or is there a delay? How are the photos relayed to Earth?
9. How does rover work? Are the rovers still working on Mars? If you love to build things, a scale model of a rover would be a great project!

It was developed during the 19th century by Irish physicist John Tyndall. Tyndallization was popular during the early 19th century for preserving and canning homegrown produce, as people still grew much of their own food during that time.

The most effective and used method of sterilization of glassware is dry heat treatment using hot air oven. On exposing the glassware to dry heat, the inhibition in growth occurs due to denaturation of proteins and oxidation of biomolecules.

The correct option is:(c) A is true, but R is false.

Explanation:

Humans are diploid with 23 pairs of chromosomes. Of this, 22 pairs are somatic and the one pair is sex chromosomes. This particular pair exists as XX in human females and XY in males. 

The presence of two X chromosomes contributes to the female phenotype while presence of only one Y chromosome is responsible for the human to be male. Females produce only X-type haploid gametes and males produce two types (X and Y) of haploid gametes. Fusion of either X or Y of male gamete with the female gamete determines the sex of the offspring.

The correct option is: (b) 2 only

Explanation:

After the removal of wastes from the kidneys, the cleaner blood is sent back through the renal veins. From Bowman’s capsule, the filtered liquid passes through tiny tubes where much of the glucose is reabsorbed and sent back to the blood in the renal vein. 

The correct option is: (d) 1 and 4

Explanation:

During exercise, the level of somatotropin goes up. Testes secrete testosterone and females’ adrenal glands secrete progesterone. Stress causes the adrenal glands to release very less amount of cortisol (a steroid hormone) than usual.

The correct option is: (c) Pitchblende

Explanation:

Radium was discovered in 1898 by Madame Curie from pitchblende a material that contains uranium.

The correct option is: (a) n-heptane

Explanation:

n-heptane has octane number of 0.0 

2-methyl heptane → 21.7 

Iso-octane → 100.00 

2, 2-dimethyl hexane → 72.5

(a) A – (s), B – (p), C – (q), D – (r)

The correct option is: (d) 2 only

Explanation:

Lead oxide deposit is harmful to engine life. Thus a small amount of ethylene dibromide is added to petrol for simultaneously removal of lead oxide.

Let a be an integer. If a is not divisible by 3 then a² ≡ 1 (mod 3), i.e., 3 divides a² - 1, and if a is odd then a² ≡ 1 (mod 8), i.e., 8 divides a² - 1. 

Note that the discriminants of the two quadratic polynomials are both squares of integers. Let a and b be integers such that m² - 4n = a² and m² + 4n = b². Therefore 8n = b² - a² and 2m² = a² + b². If 3divides m then 3divides both a and b, so 3divides n. On the other hand if 3does not divide m then 3does not divide a or b. Therefore 3divides b² - a² and hence 3divides n. 

If m is odd, then so is a, and therefore 4n = m² - a² is divisible by 8, so n is even. On the other hand, if m is even then both a and b are even. Further (m=2)² - n = (a=2)² and (m=2)² + n = (b=2)², so (b - a) = 2 is even. In particular, n = (b² - a²) = 4 is even.

The correct option is: (b) 2 1 4 3

Explanation:

 Mysore type cattle is long-horned. Gir type cattle is long-eared. Danny type cattle is called Danny. Himalaya cattle is called Dwarf type.

The correct option is: (a) 1 only

Explanation:

Beans are highly rich in proteins, potatoes and bananas are carbohydrate-rich. Banana provides an amount of sugar, minerals and vitamins and some acids (mainly malic acid).

The correct option is: (a) 1 and 2

The correct option is: (c) A is true but R is false

The correct option is: (c) 1 and 2

Explanation:

Bisexual flowers are those flowers which have both stamens (male reproductive organ) and carpels (female reproductive organs). Those plants which have only one, either male or female reproductive part are called unisexual flowers. Flowers having only male reproductive part are called staminate and the flowers having only female reproductive part are called pistillate flowers.

The correct option is: (b) 2 only

Explanation:

The largest family containing most number of genera is Asteraceae. Mushrooms are the fruiting bodies of the fungus belonging to the order Agaricales and family Agaricaceae.

The correct option is: (a) 1 only

Explanation:

All the arteries carry oxygenated blood from the heart to various parts of the body except the pulmonary artery which carries the deoxygenated or impure blood from the heart to the lungs to make it oxygenated. All the veins carry deoxygenated blood from various parts of the body towards the heart except the pulmonary vein which brings the oxygenated blood from the lungs to the heart. 

The correct option is: (a) HO41

Explanation;

One causal virus of gonorrhoea has been detected which is more aggressive than HIV in spreading AIDS and is resistance to any antibiotic. Although no infected persons are yet detected with this virus.

(d) All of these

The time period of a freely suspended magnet does not depend upon the strength of suspension.

(c) will move along with the space ship

When spoon is dropped gently, it's tangential speed is equal to the speed of spaceship, and so it revolves like a satellite.

Pleiotropy occurs when one gene will code and control the phenotype or expression of several different and unrelated traits. Pleiotropy is most often a bad thing, as many diseases are due to a gene controlling so many traits at once. 

For example, phenylketonuria is a disease caused by pleiotropy.

Due to the phenomenon of dominance a recessive allele remains obscure in the hybrid. But when two different genes which are not alleles, both affect the same character in such a way that the expression of one masks, inhibits or suppresses the expression of the other gene, it is called epistasis. The gene that suppresses is said to be epistatic, and the gene which remains obscure is hypostatic.

Complementary genes are the genes which are present on different genetic loci but interact with each other to express a single character in combination. That is they both together produce a particular phenotypic trait in an individual. Supplementary genes are the genes which include two pairs of non-allelic genes.

अल्वा, फ्यूकस, लैमीनेरिया आदि अनेक शैवालों को भोजन के रूप में प्रयोग करते हैं।

The site is the actual location of a settlement on the earth and is composed of the physical characteristics of the landscape specific to the area. Site factors include things like landforms, climate, vegetation types, availability of water, soil quality, minerals, and even wildlife.

The correct option is: (c) 1 2 3 4

Explanation:

The unit of temperature is Kelvin, power is measured in watt, pressure in Pascal and force in newton.

The correct option is: (b) 4 3 2 5

Explanation:

Heat to electrical energy conversion occurs in solar cell. Electric to sound occurs in loud speaker. Mass to heat occurs in nuclear reactor. Chemical to heat and light occurs in fuel burning

(a) nuclear magnetic resonance

Magnetic resonance imaging is based on the phenomenon nuclear magnetic resonance.

IC 1101 is the largest galaxy of our solar system which is almost a billion light years away.

IC 1101 is the largest galaxy in the solar system.

It is the single largest galaxy that has ever been found in the observable universe.This galaxy extends about 2 million light years from its core and it has a mass of about 100 trillion stars.

The profit and loss account shows  are Net profit.

(d) Profit, if there is no introduction of fresh capital.

The limitations of Single entry system of bookkeeping are as follows :

(a) As double entry system is not followed, a trial balance cannot be prepared and accuracy of accounts cannot be ensured.

(b) Correct ascertainment and evaluation of financial result of business operations cannot be made.

(c) Analysis of profitability, liquidity and solvency of the business cannot be done. This may cause a problem in raising funds from outsiders and planning future business activities.

(d) The owners face great difficulty in filing an insurance claim with an insurance company in case of loss of inventory by fire or theft.

(e) It becomes difficult to convince the income tax authorities about the reliability of the computed income.

Bill of Exchange is also Order.

Single Entry System is a Incomplete System.

Drawer in bill of exchange is a person who draws a bill.

 The correct about Single Entry System simple method.

If the due date of a bill falls on a public holiday then the bill is due on One day before the due date.

When closing capital is less than the opening capital, it denotes Loss, if there is drawing.

When closing capital is less than the opening capital, it denotes loss, if there is no drawing.

Endorsing the bill means transferring the bill to another person by the holder.

Drawer in bill of exchange is a person who draws a bill.

When closing capital is more than the opening capital, it denotes profit, if there is no introduction of fresh capital.

Endorsing the bill means transferring the bill to another person by the holder.