Answer:
x=2.4650
Step-by-step explanation:
I assume that you mean 
so let s use the ln() function

so x = ln(15)/ln(3)
x = 2.4650
The answer is the first one 6/7ab
Answer: 70 feet
explanation: 14/2=7 7x10=70
4/3pi *r3 = 972pi
Divide both side by pi
4/3 *r3 = 972
r3 = 972* 3/4
r3 = 729
r = the square root of 729 to the third power (I don't know if I'm expressing this correctly but answer is 9, hope you get that)
r = 9 that's your answer.
Hope it's correct, appreciate if you could let me know