PLEASE HELP :) A school offers two music classes, Band and Choir. Out of 66 students in Band, 36 are male. Twelve males and 42 females are in choir. There are no students who are enrolled in both classes.

Geometry ? i don't know how to do any of these.

Two blends of tea are mixed to make a blend that will be sold at the fair. black tea sells for $2.20 per pound and orange pekoe tea sells for $3.00 per pound. how much of each should be used to obtain a 4lb blend selling for $2.50 per pound?

Use set builder notation to represent the following set: { -3, -2, -1, 0}