Answer: For Question 6:
The formula for the surface area of a cylinder is given by 2πrh + 2πr^2, where r is the radius and h is the height.
Plugging in the given values, we get:
Surface area = 2π(1.75)(3.25) + 2π(1.75)^2
Surface area = 11.5625π + 10.0625π
Surface area = 21.625π
Therefore, the exact surface area of the cylinder in terms of π is 21 and 13/16 times pi square centimeters. The closest option to this is option C.
For Question 7:
The label covers the entire surface area of the cylinder except the circular top and bottom. Therefore, the surface area of the label is equal to the lateral surface area of the cylinder.
The formula for the lateral surface area of a cylinder is given by 2πrh, where r is the radius and h is the height.
Plugging in the given values, we get:
Lateral surface area = 2π(30)(20)
Lateral surface area = 1200π
Approximating using π = 22/7, we get:
Lateral surface area ≈ 1200(22/7)
Lateral surface area ≈ 3,771.43
Therefore, the label covers approximately 3,771.43 square centimeters of the wheel. The closest option to this is option B, which is 66,000/7 square centimeters, or approximately 9428.57 square centimeters.
Explanation: