Can anyone check my answers for me? URGENT

Can anyone check my answers for me?
I'm struggling and I need to make sure that I did these problems correctly:
Find the derivative of the following functions:
1. (5x-2)^(1/2)
answer: 5/2(5x-2)^(1/2)

2. (((x^3)+2)^2)((x^2)-1)
answer: 2x((x^3)+2)((4x^3)-3x+2)

3. (-3x)/ (4-x)^(1/2)
answer: 3(t-8)/2(4-x)^(3/2)

4. e^(2x^2)

answer: 4xe^((2x^2)-4)

Almost. (5/2)(5x - 2)^(-½)
For #2: http://www.flickr.com/photos/dwread/8200… but be sure to check for mistakes
For #3: sorry, no time to work it out
For #4: http://www.flickr.com/photos/dwread/8201…