Calculate the value of 16.8 x 10^7/400 Give answer in standard form

Mr angulo buy 5/8 pound of red grapes and 3/8 pound of green grapes.how many pounds of grapes did mr angulo buy

Simplify. show your work. ( 6x-2 ) ^2 ( 0.5x )^4

Liam's parents are driving three times as fast as liam is biking, but they left later than he did. if his parents caught up with him two hours after he left, how much later than liam did they leave?