1)why is iodine deficiency a problem? (green is the ruberic)

Iodine deficiency is a problem because a person can develop goiter. That's really the only reason why.

Abiotic factors are the non-living parts of an environment. These include things such as sunlight, temperature, wind, water, soil and naturally occurring events such as storms, fires and volcanic eruptions. Biotic factors are the living parts of an environment, such as plants, animals and micro-organisms