Can someone answer theses 2 short questions? i’m in a hurry.

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

The graph shows the charges for a health club in a month. make a function table for the input-output values. writes an equation that can be used to find the total charge y for the number of x classes

Is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis.