1. **State the problem:**
We need to find the exact surface area of a cylinder given its net.
2. **Identify the parts of the net:**
The net consists of a rectangle and two circles.
- The rectangle represents the lateral surface area of the cylinder.
- Each circle represents one base of the cylinder.
3. **Given dimensions:**
- Radius of each circle (base) $r = 2$ cm
- Length of the rectangle (height of the cylinder) $h = 7$ cm
4. **Formula for surface area of a cylinder:**
$$S_A = 2\pi r^2 + 2\pi r h$$
- $2\pi r^2$ is the area of the two circular bases.
- $2\pi r h$ is the lateral surface area (rectangle).
5. **Calculate each part:**
- Area of bases: $$2\pi (2)^2 = 2\pi \times 4 = 8\pi$$
- Lateral area: $$2\pi (2)(7) = 28\pi$$
6. **Add the areas:**
$$S_A = 8\pi + 28\pi = 36\pi$$
7. **Final answer:**
The exact surface area of the cylinder is **$36\pi$ cm$^2$**.
Cylinder Surface Area 85B361
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