1. what is humas 2. what are various constituents in air3. the process by which plants make their own food is called - ______

1. what is humas 2. what are various constituents in air3. the proce

1.	1. what is humas 2. what are various constituents in air3. the process by which plants make their own food is called - ______
Answer» Explanation:1. Humus is the organic matter in the soil. It is MADE of dead parts of plants and animals. Humus is so STABLE that it can persist in the soil for hundreds of years.2. Air is composed of SEVERAL gases. NAMELY Nitrogen (78%), Oxygen (21%), Argon (1%), Carbon-di-oxide (0.03%) and water vapor.Air also consists of some other gases but they are in very less amount .3. The process by which plants MAKE their own food is called Photosynthesis