John’s rectangular backyard is (10x+4) feet long and (3x+2) feet wide. What is the area of his backyard?

A. (30x^2+8) ft^2
B. (13x^2+19x+8) ft^2
C. (30x^2+32x+8) ft^2
D. (13x+6) ft^2

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.