Can someone explain to me how to do this?

When only separate discreet points are graphed it is called?

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

Boris needs to buy plastic spoons. brand a has a box 42 spoons for $2.37. brand b has a box of 72 spoons for $3.57. find the unit price for each brand. then state which brand is the better buy based on the unit price. round your answer to the nearest cent.