Help me please in maths upper pic

65% of students in your school participate in at least one after school activity. if there are 980 students in you school, how many do not participate in an after school activity?

Aconstruction worker needs to put a rectangular window in the side of a building he knows from measuring that the top and bottom of the window have a width of 8bfeet and the sides have a length of 15 feet he also measured one diagonal to be 17 feet what is the length of the other diagonal

Agatorade cooler has 36 cups of water. if a serving is 3/4 of a cup how many servings are in the cooler?