Geometry!! can someone help me with #23 please? it would mean a lot thanks :)

Abag contains 4 red, 7 blue and 5 yellow marbles. event a is defined as drawing a yellow marble on the first draw and event b is defined as drawing a blue marble on the second draw. if two marbles are drawn from the bag, one after the other and not replaced, what is p(b|a) expressed in simplest form? a. 7/16 b. 7/15 c. 14/16 d. 14/15

Asource of laser light sends rays ab and ac toward two opposite walls of a hall. the light rays strike the walls at points b and c, as shown below: what is the distance between the walls?

Suppose 38 lbs of coffee beans are required to produce 2 lbs of farmer's coffee. how many lbs of coffee beans are required to produce 309 lbs of farmer's coffee?