I need help on these last three problems.

Question

-do the following problems and express your answer in correct scientific notation.-

1. (10x10^6)/(2x10^2)

2. (9x10^-4)/(2x10^3)

3. (4x10^5)(7x10^-3)/(1.4x10^-6)

Answer 1

What trouble are you having doing these? or show your work and I'll check them.