Question

This was the question it got deleted I just need 1,2,5

Answer 1

1. The volume of the cylinder is 263
`cm^(3)`.

2. The volume of the cylinder is 12
`m^(3)`.

3. The volume of the cylinder is 3165.1
`cm^(3)`.

4. The radius of the cylinder is 3.6 cm.

5a. Area of the base is 50.2
`cm^(2)`.

5b. The curved surface area of the pencil holder is 351.7
`cm^(2)`.

5c. The surface are of the pencil holder is 452.2
`cm^(2)`.

Explanation:

1. The given shape is a cylinder, so that;

volume of a cylinder =
`\pi`
`r^(2)`h

= 3.14 x
`(3.8)^(2)` x 5.8

= 262.98128

The volume of the cylinder is 263
`cm^(3)`.

2. This is also a cylinder, but with a given diameter.

radius =
`(diameter)/(2)`

=
`(1.2)/(2)` = 0.6 m

volume of a cylinder =
`\pi`
`r^(2)`h

= 3.14 x
`(0.6)^(2)` x 10.6

= 11.98224

The volume of the cylinder is 12
`m^(3)`.

3. volume of a cylinder =
`\pi`
`r^(2)`h

= 3.14 x
`6^(2)` x 28

= 3165.12

The volume of the cylinder is 3165.1
`cm^(3)`.

4. volume of a cylinder =
`\pi`
`r^(2)`h

239 = 3.14 x
`r^(2)` x 6

239 = 18.84
`r^(2)`

`r^(2)` =
`(239)/(18.84)`

= 12.6858

r =
`√(12.6858)`

= 3.5617

The radius of the cylinder is 3.6 cm.

5. Area of the base =
`\pi`
`r^(2)`

radius =
`(diameter)/(2)`

=
`(8)/(2)` = 4 cm

Area of the base = 3.14 x
`4^(2)`

= 50.24

Area of the base is 50.2
`cm^(2)`.

5b. Area of the curved surface of the pencil holder = 2
`\pi`rh

= 2 x 3.14 x 4 x 14

= 351.68

The curved surface area of the pencil holder is 351.7
`cm^(2)`.

5c. Surface area of the pencil holder = 2
`\pi`rh + 2
`\pi`
`r^(2)`

= 2
`\pi`r(h + r)

= 2 x 3.14 x 4 (14 + 4)

= 452.16

The surface are of the pencil holder is 452.2
`cm^(2)`.