What is the probability of an event that is certain?

PLEASE HELPPP!!

A) if $50000 is invested in a bank account that pays 9.3% of interest compounded on a six-monthly basis, how much money will be in the account after 3 and 12 years? b) if matusalen's father had put $2.0 in the bank when he was born and there, how long would matusalen have had to his death (969 years later) if the interest was 7% per year composed each month and weekly?

Asocial networking site currently has 400,000 active members, and that figure is predicted to increase by 32% each year. the following expression represents the number of active members on the site after t years.

What are the solution(s) to the quadratic equation x2 – 25 = 0? o x = 5 and x = -5ox=25 and x = -25o x = 125 and x = -125o no real solution