Find out the wrong statement from the following:

Kanchan purchased gold from a jeweller. She was,however,very apprehensive about the purity of the gold purchased by her. Ultimately,she approached a person who claimed he could test its purity by making certain measurements of weight of the gold in air and water.
$(a)$ What principle was he making use of for testing purity?
$(b)$ Write the relation by which he found the relevant quantity.
$(c)$ What value did Kanchan imbibe?

The changes brought by biotic and abiotic factors in food grains that are not stored properly include:

Find out the wrong statement from the following:

$(a)$ State two differences between egg layers and broilers.
$(b)$ How can poultry fowl be prevented from various diseases? State any three methods.

Poultry farming is undertaken to raise which of the following?
$(i)$ Egg production
$(ii)$ Feather production
$(iii)$ Chicken meat
$(iv)$ Milk production