MATH HELP!!!!!

Sorry burberrygirl but I can't understand a thing about the first two problem since they're expressed ambiguously( at least to me)
Here's my answer for the 3rd and 4th problem:
3) A = 1/(9x^[(-2y)^(-1)]) ( I presumed that 9x^(-2y) and then -2y^(-1), right)
Ok, we will seperate this expression into 3 parts:
The first one: -2y^(-1)=1/(-2y)
The second one: 9x^[(-2y)^(-1)]=9x^[1/(-2y)]
The third one: A= 9x^[1/2y]
4) x(2-x)-x(3-x)= x[(2-x)-(3-x)]=x(2-x-3+x)=5x.
I am deeply sorry if there is anything wrong here. I am a Vietnamese and my knowledge of Maths in English is not so good. If you find anything vague or enigmatic or any flaw I've made in this post. Please reply here or contact me by email.

wakarimasen !!!
some mathematical expression is better with parentheses....