The equation shown has an unknown number. What is blank Divided three sevenths equals seven fifteen

Aparallel system functions whenever at least one of its components works. consider a parallel system of n components, and suppose each component works independently with probability 0.5. find the conditional probability that component n works given that the system is working

The function v(r)=4/3pir^3 can be used to find the volume of air inside a basketball given its radius. what does v(r) represent

Hi i’m not sure how to do question 20 if u could explain how to do it that’d b great