8a to the power of 6 times a to the power of 4 over 4a to the power of -3

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much

Abag contains 3 red marbles, 2 blue marbles, and 2 green marbles. one marble is picked, then another marble. assume that the selections are made with replacement. a) find the probability of picking two red marbles with replacement. b) find the probability of picking a red marble and a blue marble. assume the selections are made without replacement. c) find the probability of picking two red marbles without replacement. d) find the probability of picking a red marble and a blue marble without replacement.

What is the radius of a circle with an area of 78.5 cubic inches? use 3.14 for pie