since the diameter of the base of the cylinder is 6 feet, then its radius is half that, or 3 feet.
![\bf \textit{volume of a cylinder}\\\\ V=\pi r^2 h~~ \begin{cases} r=radius\\ h=height\\[-0.5em] \hrulefill\\ r=3\\ h=9 \end{cases}\implies V=\pi (3)^2(9)\implies V=81\pi](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Bvolume%20of%20a%20cylinder%7D%5C%5C%5C%5C%0AV%3D%5Cpi%20r%5E2%20h~~%0A%5Cbegin%7Bcases%7D%0Ar%3Dradius%5C%5C%0Ah%3Dheight%5C%5C%5B-0.5em%5D%0A%5Chrulefill%5C%5C%0Ar%3D3%5C%5C%0Ah%3D9%0A%5Cend%7Bcases%7D%5Cimplies%20V%3D%5Cpi%20%283%29%5E2%289%29%5Cimplies%20V%3D81%5Cpi)
]Answer:

Step-by-step explanation:
Substitute the value of the variable into the equation and simplify.

Solve it out.
Multiply / divide / add / subtract everything out.
Answer:
-6
Step-by-step explanation:
The composite number is A.63. 1 is neither a prime or composite. 19 is a prime. 0 is a trick honestly, it isn't a prime or a composite
Speed = Distance/Time. Let speed be V, distance D and time T
a)Given: D₁ =45km, V₁=x km/h
V₁=D₁/T
V₁=45/T OR T= 45/V₁
b) Given : D₂ =48 km and V₂ = V₁ + 4 km/h
V₂ = 48/T, but V₂ = V₁+4, then:
V₁+4 = 48/T OR T=48/(V₁+4). Since Time is same, then we can write:
45/V₁ =48/(V₁+4), solve for V₁:
45V₁ + 180 = 48V₁
3V₁ =180 and V₁ = x = 60 km/h