Help me pls on these

first one is A) 21

second one is D) 150

Step-by-step explanation:

first one : add all marbles  =  10

there are 3 red

chances of picking a red 3/10 or 30 percent or .3

multiple 70 by .3 and get 21

second one:

A = 6 (Surface area of cube)

600 = 6

a = 10

half of 10 is 5

6() = 150

  n=   0.0000 - 0.3750 i  

  n=   0.0000 + 0.3750 i

step-by-step explanation:

one of these should be correct