Respuesta :

Answer:

1. The volume of the cylinder is 263 [tex]cm^{3}[/tex].

2. The volume of the cylinder is 12 [tex]m^{3}[/tex].

3. The volume of the cylinder is 3165.1 [tex]cm^{3}[/tex].

4. The radius of the cylinder is 3.6 cm.

5a. Area of the base is 50.2 [tex]cm^{2}[/tex].

5b. The curved surface area of the pencil holder is 351.7 [tex]cm^{2}[/tex].

5c. The surface are of the pencil holder is 452.2 [tex]cm^{2}[/tex].

Step-by-step explanation:

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

volume of a cylinder = [tex]\pi[/tex][tex]r^{2}[/tex]h

                                  = 3.14 x [tex](3.8)^{2}[/tex] x 5.8

                                  = 262.98128

The volume of the cylinder is 263 [tex]cm^{3}[/tex].

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

radius = [tex]\frac{diameter}{2}[/tex]

          = [tex]\frac{1.2}{2}[/tex] = 0.6 m

volume of a cylinder = [tex]\pi[/tex][tex]r^{2}[/tex]h

                                  = 3.14 x [tex](0.6)^{2}[/tex] x 10.6

                                  = 11.98224

The volume of the cylinder is 12 [tex]m^{3}[/tex].

3. volume of a cylinder = [tex]\pi[/tex][tex]r^{2}[/tex]h

                                      = 3.14 x [tex]6^{2}[/tex] x 28

                                      = 3165.12

The volume of the cylinder is 3165.1 [tex]cm^{3}[/tex].

4. volume of a cylinder = [tex]\pi[/tex][tex]r^{2}[/tex]h

239 = 3.14 x [tex]r^{2}[/tex] x 6

239 = 18.84 [tex]r^{2}[/tex]

[tex]r^{2}[/tex] = [tex]\frac{239}{18.84}[/tex]

   = 12.6858

r = [tex]\sqrt{12.6858}[/tex]

 = 3.5617

The radius of the cylinder is 3.6 cm.

5. Area of the base = [tex]\pi[/tex][tex]r^{2}[/tex]

radius = [tex]\frac{diameter}{2}[/tex]

           = [tex]\frac{8}{2}[/tex] = 4 cm

Area of the base = 3.14 x [tex]4^{2}[/tex]

                            = 50.24

Area of the base is 50.2 [tex]cm^{2}[/tex].

5b. Area of the curved surface of the pencil holder = 2[tex]\pi[/tex]rh

                                                                    = 2 x 3.14 x 4 x 14

                                                                     = 351.68

The curved surface area of the pencil holder is 351.7 [tex]cm^{2}[/tex].

5c. Surface area of the pencil holder = 2[tex]\pi[/tex]rh + 2[tex]\pi[/tex][tex]r^{2}[/tex]

                               = 2[tex]\pi[/tex]r(h + r)

                                = 2 x 3.14 x 4 (14 + 4)

                                = 452.16

The surface are of the pencil holder is 452.2 [tex]cm^{2}[/tex].