The surface area of a cylinder is the sum of the top + bottom + body, right?
The top and the bottom are circles with the same radius 3.5 . And we know that the area of a circle is r^2pi, (don't forget we have 2 circle, so, the answer must be multiplied by 2)
Now, the body: the body is just a rectangular with the width is the height of the cylinder and the length is the circumference of the circle.
The circumference = 2 r pi
the height is given
All you need to do is to calculate them and add them up. You need to work out to get the answer.