Am currently doing a practice sheet but cant do half of it, need some help please. Here goes

**Determine the continuity of the function at the given points. **

f(x) = -1, for x =-2

0.5, for x not equal to -2

at x = -2 and x = -3

**Answer the question. **

Is the function given by

f(x) =x+4/ x^2 -9x+8

continous at x = 1? Why or why not?

**Find the intervals on which the function is continuous. **

Is the function given by

f(x) = 1/ x+1^2 +2

continuous on ℛ? Why or why not?

**Find a simplified difference quotient for the function. **

f(x) = 9^x3

**Find a simplified form of the difference quotient for the function. **

f(x) = square root of x-4

**Calculate the requested derivative from the given information. **

Given f(u) = u-1/u+1, g(x) = u = square root of x, find (f ∘ g)'( 4).