Question

the volume of a cylinder whose radius is 2r and height h/4cm is​

Answer 1

Surface area of cylinder is A=2πr(r+h)

Since, cylinder A has radius r=2 cm and height h=4 cm.
Thus,

A=2πr(r+h)=2×3.14×2(2+4)=12.56×6=75.36

Therefore, the surface area of cylinder A is 75.36 cm
Also, cylinder B has radius r=1 cm and height h=5 cm.

A=2πr(r+h)=2×3.14×1(1+5)=6.28×6=37.68
Therefore, the surface area of cylinder B is 37.68 cm

Hence, cylinder A has greater surface area.

Answer 2

Question:

The volume of a cylinder whose radius is 2r and height h/4cm is

Answer:

$\: volume \: of \: a \: cylinder \: \\ = \pi {r}^{2} h \\ = \pi \times 2r \times \frac{h}{4} \\ = \frac{\pi \times r \times h}{2} \\ = \frac{22}{7} \times r \times h \times \frac{1}{2} \\ = \frac{11rh}{7} \\ = 1.5714rh$

$\red {be \: brainly \: }$