Need help with a few math problems

I had trouble with these four questions any help would be great!

1. Identify the center and radius of the circles represented by the following questions

(a) 3x² - √3x+3y²-y+ 1/12=0 (b) 12x² + 12y²+42y=0

2. Let f(x)= 1/√x-2 and g(x)=√x+1.

(a) Find the domain of each function.

(b) Find the domain of (g/f)(x)

3. Determine whether the functions are even, odd, or neither.

(a) f(x)= x²/√x+1 (b) g(x)=x³ - √x-7

4. Let f(x)= x^5/120- x³/6 + x.

(a) Find the local minima and maxima.

(b) Determine where the function is increasing and decreasing.

*Sorry I didn't know how to put them in correctly but the / is divided by and the ^5 is to the fifth power and the √ is the square root

Any help is greatly appreciated