Acircle has a radius of 9 centimeters. what is the length of its diameter?

Offering 30 if a plus b plus c equals 68 and ab plus bc plus ca equals 1121, where a, b, and c are all prime numbers, find the value of abc. the answer is 1978 but i need an explanation on how to get that.

If olu is twice as old as funmi if the sum of their ages is 60 how old is olu

When 142 is added to a number the result is 64 more then 3 times the number. option 35 37 39 41