Question

Please please please help. thank you.

Answer 1

Lets get started :)


The First question:
Diameter = 20 ft
Radius =
`(1)/(2)` of 20 (diameter) = 20 ft

Area formula of a circle is
A =
`\pi`r²
=
`\pi`(10)²
=100
`\pi` ft²
≈ 314 ft²

The answer will be the second option

The Second question:
radius of circle = 12mm divided into 20 sectors area

A =
`\pi`r²
=
`\pi`(12)²
= 144
`\pi` ft²

Divide into 20 equal sector areas =
`(144 \pi )/(20) = 7.2 \pi`

≈ 22.6 mm²

Your answer will be the third option

The Third Question:

90°, sector area = 36
`\pi` , Radius = ?


`(angle)/(360) = (sector)/( \pi (r)^2)`

`(90)/(360) = (36 \pi )/( \pi r^2)`

`\pi` and
`\pi` cancels out

We can now cross multiply
360 × 36 = 90r²
12960 = 90r²

Divide by 90 on either side


`(12960)/(90) = (90r^2)/(90)`
144 = r²

Take squareroot

`√(144) = x`
x = 12 in

Your answer will be the third option