Which is greater 3.95, 3 5/6, 3 4/5

The ratio pv to nrt is plotted against pressure for ch4 at 0°c and 200°c. why does the curve for 0°c drop below the horizontal line for an ideal gas whereas the curve for 200°c does not?

If f(x) = x+8 and g(x) = 4x- 3, find (f+g)(x)

If x = -2, then x 2-7x+10 equals a. 0 b.20 c.28