Question

plz answer 7 ,9 ,11 number​

Answer 1

(As.7) Silver and gold can be found in pure state in nature as they are extracted from the land and mountains in their raw form so they are pure in their nature,whereas iron is not pure as it is extracted from its ore and then industrilised which means chemicals are added so it is not pure in its nature as compared to silver and gold.

(As.9) Environment is polluted by use of insecticides as insecticides are manufactured by the use of chemicals which then are added in the soil in the form of insecticides, then harm the useful microbes in the soil thus leading to degradation in the fertility of soil.