1. **Stating the problem:** We need to find the volume of concrete required for a slab with thickness 7 cm (0.07 m) and the given stepped rectangular shape with dimensions as described. 2. **Convert thickness to meters:** Thickness $= 7\text{ cm} = 0.07\text{ m}$. 3. **Calculate the total area of the slab's top surface:** The shape can be divided into three rectangles stacked vertically: - Top rectangle: width $8\text{ m}$, height $1\text{ m}$ - Middle rectangle: width $3\text{ m}$, height $2\text{ m}$ - Bottom rectangle: width $14\text{ m}$, height $2\text{ m}$ (since total height is 5 m, and the first two steps add up to 3 m, the remaining height is $5 - 3 = 2$ m) 4. **Calculate each area:** - Top area $= 8 \times 1 = 8\text{ m}^2$ - Middle area $= 3 \times 2 = 6\text{ m}^2$ - Bottom area $= 14 \times 2 = 28\text{ m}^2$ 5. **Sum the areas:** $$\text{Total area} = 8 + 6 + 28 = 42\text{ m}^2$$ 6. **Calculate the volume:** $$\text{Volume} = \text{Area} \times \text{Thickness} = 42 \times 0.07 = 2.94\text{ m}^3$$ 7. **Final answer:** The volume of concrete needed is **2.94 cubic meters**.