Cos(5pi/3) = ? Help please

What point is the projection of q on a) r b) s c) t

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.

Find the multiplicative inverse of 8-12i