Answer: 15
Step-by-step explanation: Use the formula: 
Remember
should always be the hypotenuse or the longest side.
---> evaluate the exponents
----> subtract 12544 to the other side
---> take the square root of both sides

Step-by-step explanation:
We have,
Diameter of cylinder, d = 39.2 mm
Radius, r = 19.6 cm
Height of the cylinder, h = 39.2 mm
It is required to find the surface area of this cylinder. The formula of the surface area of cylinder is given by :

Putting all values we get :

You just combine like terms
So 4d + - d = 3d
And 3x + 2x = 5x
So the answer is 3d + 5x
Answer:
answer is a
Step-by-step explanation: