Simplify the expressions

1) 2 ^3 sq rt 5 - 4 ^3 sq rt 40 + 3 ^3 sq rt 135

2) sq rt p^7 q^3 - sq rt p^5 q^9 + sq rt p^9 q

3) sq rt b^3 * ^4 sq rt b^3

4) sq rt 16 - 8x + x^2

I am completely lost I try researching everything for help I can only do some of the problems half way and get stuck.