1. **Problem statement:** Calculate the surface area of a pyramid with given base and slant heights.
2. **Formula:** The surface area $A$ of a pyramid is given by
$$A = B + \frac{1}{2} P l$$
where $B$ is the base area, $P$ is the perimeter of the base, and $l$ is the slant height.
3. **Step-by-step solution for the first pyramid:**
- Given: base side length $4$ cm, slant height $6$ cm, base area $64$ cm$^2$ (likely a square base).
- Calculate perimeter $P$ of the base: Since base is square with side $4$ cm,
$$P = 4 \times 4 = 16 \text{ cm}$$
- Calculate lateral surface area:
$$\frac{1}{2} P l = \frac{1}{2} \times 16 \times 6 = 8 \times 6 = 48 \text{ cm}^2$$
- Total surface area:
$$A = B + \frac{1}{2} P l = 64 + 48 = 112 \text{ cm}^2$$
4. **Explanation:** The base area is the area of the square base. The lateral surface area is the sum of the areas of the triangular faces, each with base equal to a side of the base and height equal to the slant height.
5. **Final answer:** The surface area of the pyramid is $112$ cm$^2$.
Since multiple pyramids are shown but only the first is solved here, the count of distinct problems is 8 as per the input.
Pyramid Surface F19867
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