1. 7 ÷ 3 = y. y = 2. true or false, the sum of zero and an addend is zero

Can someone check if i did this correct. it’s number 4 if you’re wondering.

The volume of gas a balloon can hold varies directly as the cube of its radius. imagine a balloon with a radius of 3 inches can hold 81 cubic inches of gas. how many cubic inches of gas must be released to reduce the radius down to 2 inches?

Atown has a population of 17000 and grows at 2.5% every year. to the nearest year, how long will it be until the population will reach 19600?