An electronic computer can do 10 ^ 12 calculations per second. How many calculations can it do when it works for 5 × 10 ^ 6 seconds?

An electronic computer can do 10 ^ 12 calculations per second. How many calculations can it do when it works for 5 × 10 ^ 6 seconds?

5x10 ^ 6x10 ^ 12 = 5x10 ^ 18 times