Answer: Ethan's cylinder has a larger total surface area.
Explanation:
You total surface area of a cylinder can be calculated with the following formula:

Where "r" is the radius and "h" is the height of the cylinder,
Then:
1) Total surface area of Tommy's cylinder
Since the radius is half the diameter:

Knowing that:

You can subsitute values into the formula and find the total surface area:

2) Total surface area of Ethan's cylinder
Knowing that the radius is half the diameter:

And having:

You can subsitute values into the formula and find the total surface area:

Therefore, Ethan's cylinder has a larger total surface area.