What is the product (7x10^-5) (5x10^-8)

Well 7 x 10^-5 would mean you moved the decimal 5 Times because the power at the end of 10 is how many times the decimal is moved till it's a number greater or equal to 1. So the scientific notation of that is: 0.00003

The - 5 means that it was moved to the right. Positive always means left. Negative is always right.