how do i solve this step by step

Answer:
4) x^10
Step-by-step explanation:
1) If two numbers have the same base (i.e. x^3 and x^4) and you are multiplying them you just add the exponents. Therefore x^3*x^4 would be x^(3+4) which equals x^7.
2) When dividing similar bases you have to subtract the exponents. If we have x^18÷x^8 that is equivalent to x^(18-8) which gives us x^10.
3) If we have (x^3)^3 we will need to multiply the exponents. Therefore (x^3)^3 is equivalent to x^(3*3) which gives us x^9.
4) (x^2*x^4)^4÷x^8
First do what's in the parentheses,
(x^2*x^4) = x^6
Next do the exponents,
(x^6)^3 = x^18
Lastly the division,
x^18÷x^8 = x^10
x^10 is our answer.