the surface area of a sphere is
[tex]4\pi r^2[/tex]and r=diameter/2
so r= 3.75
and
[tex]surfacearea=4\cdot\pi\cdot3.75^2=176.71cm^2[/tex]and the volume of a sphere is
[tex]\frac{4}{3}\cdot\pi\cdot r^3[/tex]so:
[tex]\text{volume}=\frac{4}{3}\cdot\pi\cdot3.75^3=220.89cm^3[/tex]