I need help solving these problems please help as it looks like greek to me. I know how to simplify but the next step is confusing.

. Simplify the following expression, and rewrite it in an equivalent form with positive exponents.
-18xy^5/54x^3y^6
2. Raise the quantity in parentheses to the indicated exponent, and simplify the resulting expression.
(-5x^3y)^2
3.Short Answer: Simplify the following expression, and rewrite it in an equivalent form with positive exponents.
(-2x^2)^-4
4. Multiply the expressions, and simplify.
(5x-3y-2) • (3x3y-4)

Question

I need help solving these problems please help as it looks like greek to me. I know how to simplify but the next step is confusing. 

. Simplify the following expression, and rewrite it in an equivalent form with positive exponents.
-18xy^5/54x^3y^6
2. Raise the quantity in parentheses to the indicated exponent, and simplify the resulting expression.
(-5x^3y)^2
3.Short Answer: Simplify the following expression, and rewrite it in an equivalent form with positive exponents.
(-2x^2)^-4
4. Multiply the expressions, and simplify.
(5x-3y-2) • (3x3y-4)