How u get the answer? and what it is?

Volume of a cylinder with a radius of 13 in and height of 30 in

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.

Which equation represents a direct linear variationa. y=x2b. y=2/5xc. y=1/xd. y=x+3