Think about how exponents with a base 10 work. 10^1 = 10, 10^2 = 100, 10^3 = 1000. It's just add a zero to the right side as you go up.
Then think about 10^0. Anything to a zero power is 1. Only way to go is into negative exponents now. If for positive exponents on 10 we add a zero to the right side, then for negative exponents we add them to the left. Only difference is we have a decimal.
10^(- 1) = 0.1 10^(- 2) = 0.01 10^(- 3) = 0.001
And then your answer
10^(- 4) = 0.0001
Hopefully that explanation makes sense. Exponents can be rough to explain when you're not face-to-face or using some sort of live animation to talk through it. If you're still confused, I'd suggest talking to your instructor.
