help with some math questions?

1. list all possible zeros of the following question:2x^4 - 3x^2 + -4=02. write as a sum of difference of logs of x,y, and zlog(x^5z^3/y^7)3. find the sum of the first 500 terms50,25,12.5,6.25,....4. left f(x)= 1/(x+5) and g(x) = (x +3)^1/2 find the domain of f+g,f-g,fg, and g/f