(1) As we know that the surface area of the cylinder is given by the formula
surface Area=[tex] 2\pi rh+2 \pi r^2 [/tex]
If the radius and height are tripled, then we get
surface Area=[tex] 2\pi *3r*3h+3*2 \pi (3r)^2 [/tex]
surface are =[tex] 9*2\pi rh+9*2 \pi (r)^2=9(2\pi rh+2 \pi (r)^2) [/tex]
The surface area is multiplied by 9.
(2) As we know that the surface area of the rectangular prism is given by
Surface area=[tex] 2(wl+hl+hw)\\ [/tex]
Now if the length, width, and height are halved, we get the surface area as
surface area=[tex] 2(\frac{1}{4}wl+\frac{1}{4}hl+\frac{1}{4}hw) =2*\frac{1}{4}(wl+hl+hw)\\ [/tex]
surface area=[tex] \frac{1}{2}(wl+hl+hw)\\ [/tex]
The surface area is multiplied by 1/2.