Use the formulas for a cylinder: r = 7 mm h = 4mm sa =

S.A = 483.87mm²

Step-by-step explanation:

Given parameters:

radius of the cylinder(r) = 7mm

height(h) = 4 mm

unknown is the surface area of the cylinder which is S.A

Solution

The surface area of a body is the total area covered by the outermost part of such a body. A cylinder has top and bottom circles with a trunk.

            The surface Area of cylinder is given as = 2πrh + 2πr²

Now we slot in the appropriate parameters:

           S.A = (2 x π x 7 x 4 ) + (2 x π x 7²)

           S.A = (175.95 + 307.92)mm²

          S.A = 483.87mm²

The surface area of given cylinder is  483.56 square mm

Step-by-step explanation:

Points to remember

Surface area of cylinder = 2πr(r + h)

Where r - Radius of cylinder

h - Height of cylinder

To find the surface area of cylinder

Here r = 7 mm and h = 4 mm

Surface area = 2πr(r + h)

 = 2 * 3.14 * 7(7 + 4)

 = 483.56 square mm

The surface area of given cylinder is  483.56 square mm

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number of bracelets * x + shipping charge = total cost

so

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