Solve please and SHOW UR WORK

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.

Which expression shows the sum of the polynomials with like terms grouped together

Cos^2x+cos^2(120°+x)+cos^2(120°-x)i need this asap. pls me