1.    a)    multiplication:    \(x^a\cdot x^b=x^{a+b}\)
        b)    power of a power:     \(\left(x^a\right)^b=x^{ab}\)
\(\left(x^a\right)^b=x^{ab}\)        c)    division:    \(\frac{x^a}{x^b}=x^{a-b}\) 
        d)    power of a product:    \(\left(x\cdot y\right)^a=x^a\cdot y^a\)
\(\left(x\cdot y\right)^a=x^a\cdot y^a\)
2.    a)    The surface area will increase by a factor of 16:    \(4\pi\left(4r\right)^2=16\left(4\pi r^2\right)\)
\(4\pi\left(4r\right)^2=16\left(4\pi r^2\right)\)