Question

Va rog.
Raza unei are lungimea de 4 cm.Aria sferei este egala cu.....cm?
Mersiii.

Answer 1

$R=4 \ cm \\ A=4 \pi R ^{2} \\ A=4 \pi 4 ^{2} \\ A=4 \pi 16 \\ \boxed{A=64 \pi} .$