Answer: The surface area of Ming's bundle of pencils is approximately 9.8 cm².
Step-by-step explanation:
To find the surface area of the bundle of pencils, you need to calculate the lateral surface area of the cylinder plus the area of the two circular bases.
First, let's find the lateral surface area of the cylinder:
Lateral surface area = π * diameter * height
Given that the diameter is 0.5 cm and the length (height) is 19 cm:
Lateral surface area = 3.14 * 0.5 cm * 19 cm = 9.41 cm²
Now, let's find the area of the circular bases:
Area of one circular base = π * (radius)^2
Since the diameter is 0.5 cm, the radius is half of that, which is 0.25 cm.
Area of one circular base = 3.14 * (0.25 cm)^2 = 0.19625 cm²
Since there are two circular bases:
Total area of circular bases = 2 * 0.19625 cm² = 0.3925 cm²
Now, add the lateral surface area and the area of the circular bases to get the total surface area:
Total surface area = Lateral surface area + Total area of circular bases
Total surface area = 9.41 cm² + 0.3925 cm² = 9.8 cm²
So, the surface area of Ming's bundle of pencils is approximately 9.8 cm².
