To solve this problem, we must find the volume of the sandbox.
![V=l\cdot w\cdot d](https://img.qammunity.org/2023/formulas/mathematics/college/z1dd4ycq0l3vurtevb3w21xq8xnx41898l.png)
Where:
![\begin{gathered} l=30m \\ w=26m \\ d=4m \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/vrra3jy8iqea3q2cdxgg299j2y1cv2ubsz.png)
Now, we replace and solve:
![\begin{gathered} V=30m\cdot26m\cdot4m \\ V=3120m^3 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/jf3ttz02fhr0ov8x91purkijuqxfi5lx96.png)
The A answer is 3120 cubic meters
Now, for question "b" we must find how many cubic meters are 89% of its capacity, that is 89% of the capacity of the 3120 cubic meters.
For this, we multiply the total capacity of the sandbox by 0.89.
![3120\cdot0.89=2776.8](https://img.qammunity.org/2023/formulas/mathematics/college/d6pe9sf7842meluu4c4lsao2xsrf0i7930.png)
The A answer is 2776.8 cubic meters