4.2.3.Befine a balanced chemical equation. Why should an equation be balanced?Ca(OH)2 +Balance the given chemical equation:HNO, - Ca(NO)exothermie.Deline combination reaction. Give one example of a combination reaction which5.6.What is rancidity? Mention any two ways by which rancidity can be prevented.equations for these reactions.What is the difference between displacement and double displacement reactions?7. Decomposition reactions require energy either in the form of heat or light or electrifor breaking down the reactants. Write one equation each for decomposition reactions wheenergy is supplied in the form of heat, light and electricity.BIOLOGY (MM-14)Answer the following questions:Q1. How does the plant cope up with lack of water in desert conditions?Q2. Why is the rate if breathing much faster in aquatic organisms than those of terrestrialorganisms?Q3. In the experimental setup to show that" CO2 is given out during respiration". Namesubstance taken in the small test tube kept in the conical flask. State its functions and theconsequences of its use.OR(a) Define excretion.(b) Name the basic filtration unit present in the kidney.Q4. Draw a diagram of the human urinary system and label in it.a)Kidney b)Ureter c)Urinary Bladder dUrethraQ5. Differentiate between Arteries and Veins (any four).Q6. Write one feature that is common to each of the following pairs of the term/organsi) Glycogen and starch ii) chlorophyll and hemoglobin iii) Gills and lungsQ7.Write the functions of each of the followingi)Bile ii) HCI i) villi.PHYSICS (MM-13)1. How is ammeter connected in a circuit to measure the current?2. The magnetic field for a current carrying conductor is anticlockwise, if the conductor was heldeast-West direction, what is the direction of current?3. State the right hand thumb rule4. Keeping the Potential difference constant, the residence of circuit is doubled. By whatdoes the current change in the circuit?