Ahemispherical wooden bowl has an internal radius of 8cm and an external radius of 9cm
calculate the volume of the wood

Step-by-step explanation:

We have a hemisphere with a radius 9 cm with a hemisphere cut out with radius 8cm.

Calculate a volume of a larger hemisphere and subtract from it a volume of smaller hemisphere.

The formula of a volume of a sphere:

R - radius

Therefore the formula of a volume of a hemisphere:

The volume of the larger hemisphere:

The volume of the smaller hemisphere:

The volume of wood:

Substitute:

454.5 cm³

Step-by-step explanation:

The volume (V) of a sphere is calculated using formula

V= πr³ ← r is the radius

Thus the volume (V) of a hemisphere is

V = × πr³ = πr³

= -

                               = π × 9³ - π × 8³

                              = π (9³ - 8³)

                             = π (729 - 512 )

                            = π × 217 ≈ 454.5 cm³

the amount you'd have after the work is $1.55

step-by-step explanation:

you subtract 95% from $31.

the answer is b