Questions

When exports are greater than imports, net exports are positive and similarly, when imports are greater than exports, net exports are negative.

When a country imports goods, it buys them from foreign producers. The money spent on imports leaves the economy, and that decreases the importing nation's GDP.

The law of conservation of mass states that in any closed system the mass of the system is neither created nor destroyed over time i.e, the mass cannot be changed overtime.

Hence, the given statement is true.

Deficiency of Iodine cause Goiter also called Enlarged Thyroid. It doesn't give any pain but difficult to swallow and breath are its causes.

Economic growth is measured by the percentage of gross domestic product. GDP refers to the total value of goods and services produced in the country.