Paheli watched her grandmother making mango pickle. After she bottled the pickle, her grandmother poured oil on top of the pickle before closing the lid. Paheli wanted to know why oil was poured. Can you help her understand why? Open Answer »
Give reasons for the following. (i) Fresh milk is boiled before consumption while processed milk stored in packets can be consumed without boiling. (ii) Raw vegetables and fruits are kept in refrigerators whereas jams and pickles can be kept outside. (iii) Farmers prefer to grow beans and peas in nitrogen deficient soils. (iv) Mosquitoes can be controlled by preventing stagnation of water though they do not live in water. Open Answer »
Give reason for Mosquitoes can be controlled by preventing stagnation of water though they do not live in water. Open Answer »