PreCalculus/Calculus Homework Help!?

I have a few problems from my summer homework packet that I don't know how to do at all, so I was wondering if anyone can help me? --I'm not allowed to use a calculator on any of these problems, and I would like it if you were to show me how to do these problems step-by-step

1) if c(x) = cos(sin^(-1)x), what is the range of c?

2) log(base 1/b)x =

3) a parametric representation for the line containing (-3, 6) and (2, 10) is...

4) solve for x: 2x = 7^(1+log(base 7)4)

5) f(a + b) = f(a) x f(b) is true if f(x)=
     a. x
     b. log(base c)x
     c. sin x
     d. 1/x
     e. 3^x

6) which of the following functions is periodic with period (pi)
     a. y=sin x
     b. y=(pi)x
     c. y= lcos xl
     d. y= (pi)
     e. y= sin (pi)x