. . .3x^6 - 24x^5 + 18x^4

What I got was is:

. . .3x^4(x^2 - 8x + 6)

Did I do that right?

2) Divide and write the answer without exponents:

. . .(4 * 10^5) / (2 * 10^(-2))

I have no clue what to do.

3) Use the exponent rule to simplify the expression. Assume the variables represent nonzero real numbers.

. . .[(m^8 n)^(-2)] / [m^(-4) n^7]

I don't know what to do for this one.

4) Perform the indicated operation, and simplify your answer:

. . .[(x^2 - 3x - 18) / (x^2 - 6x + 9)] / [(x - 6) / (x - 3)]

Again...I don't know what to do.