mohon bantuannya gumawo

v tabung = phi.r².t
= phi.6².20
= 36.20.phi
= 720 phi

v kerucut = 1/3.v tabung
= 1/3.720 phi
=240 phi

v tabung di luar kerucut
= 720 phi - 240 phi
=480 phi

jadi jawabannya C

^^