(N/A) The physical symptoms of goitre and hypothyroidism are as follows:
$(i)$ During hypothyroidism,the metabolic rate of the body decreases.
$(ii)$ Increased sleep and lethargy are observed along with increased body weight.
$(iii)$ Swelling of the neck (goitre) and sometimes swelling of the legs is observed.
$(iv)$ During goitre,the thyroid gland enlarges significantly.
$(b)$ Others can be informed about the importance of iodised salt through posters,banners,or by organizing small awareness programs in the locality.
$(c)$ Iodine is a non-metal with the symbol $I$.
$(d)$ Iodine is a non-metal that appears as a metallic grey solid and turns into a violet gas upon heating. It has a boiling point of about $457.4 \ K$ and a density of about $4.933 \ g/cm^3$. Iodine undergoes sublimation when heated.
$(e)$ There is no significant difference in the chemical structure of the base salt. The main difference is that normal salt is primarily $NaCl$,whereas iodised salt has a small amount of iodine compounds (like potassium iodide) added to $NaCl$,which is an essential micronutrient. This is necessary because iodine levels are low in many soils worldwide,leading to a deficiency in crops and subsequently in humans,causing goitre.