Answer:
[tex]B_2=4\pi r^2[/tex]
see the explanation
Step-by-step explanation:
we know that
The area of the base of a cylinder is given by the formula
[tex]B=\pi r^{2}[/tex]
where
r is the radius of the circular base
If the radius is doubled
then
[tex]r=2r[/tex]
The new base area is
[tex]B_2=\pi (2r)^{2}[/tex]
[tex]B_2=4\pi r^2[/tex]
so
[tex]B_2=4B[/tex]
therefore
The new area of the base is 4 times the area of the original base
