What do the angles in a triangle add up to

Cora bought a package of erasers. there are 4 pink erasers and 12 blue erasers. what is the ratio of pink erasers to blue erasers?

The border line of the linear inequality 4x + 7y < 5 is dotted true or false?

I’m on question 7 it says a covered water tank is in the shape of a cylinder the tank has a 28 inch diameter and a height of 66 inches to the nearest square inch what is the surface area of the water tank