Answer:282.6 cm²
Explanation:
The formula for the surface area of a cylinder is 2πr(r+h) where r is the radius and h is the height.
Since the diameter is given, we can find the radius by dividing the diameter by 2, so r = 6/2 = 3 cm.
Then we can plug in the values into the formula:
2πr(r+h) = 2π(3)(3+12) = 2π(3)(15) = 90π cm²
To round the answer to the nearest tenth, we can use the following method:
If the digit in the thousandths place is less than 5, we keep the hundredths digit as is.
If the digit in the thousandths place is greater than 5, we round up the hundredths digit.
Since π is an irrational number it can't be rounded to the nearest tenth. But an approximation for π is 3.14 and 90π is approximately 282.6 cm².