To calculate the surface area of a cylinder, we can use the following formula.
S=2π rh+2π r^2
In this formula, r is the radius and h is the height of the cylinder. From the diagram above we can see that the diameter of the base is 24 cm. Recall that the diameter of a circle is twice the length of the radius. With this in mind, we can find the length of the radius by substituting d=24 into the formula below.