UPSC CDS Math Volume and Surface Area Questions

We have,
The diameter of right circular cylinder =20cm
∴2r=20cm
⇒r=10cm
We know that curved surface area =2πrh sq. units
Given that curved surface area =1000cm2
⇒2πrh=1000
⇒‌‌π×20h=1000
⇒‌‌h=‌

50

π

cm
We know that volume of cylinder =πr2h‌ sq. units ‌
‌‌=π×(10)2×‌

50

π

=5000cm3