In a junkyard, 3/5 of the vehicles are trucks, and 2/6 of the trucks are black, what fraction of the vehicles in the junkyard or black trucks?​

Tom can paint the fence in 12 hours, but if he works together with a friend they can finish the job in 8 hours. how long would it take for his friend to paint this fence alone?

Math i have no idea how to do a and b

The graph of a curve that passes the vertical line test is a: