Math is i watched youtube videos on this question and ask people how to do it but i still can't do it

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

Aline has a slope of and a y-intercept of –2. what is the x-intercept of the line?

Arestaurant chef made 1 1/2 jars of pasta sauce. each serving of pasta requires 1/2 of a jar of sauce. how many servings of pasta will the chef be bale to prepare using the sauce?