1. **State the problem:** We need to determine if filling the water tower to 80% of its volume will keep the weight of the water under the maximum limit of 5,000 pounds. 2. **Given data:** - Maximum weight limit: 5,000 pounds - Weight of water per cubic foot: 62.4 pounds/ft³ - Volume of water tower: $V = 66$ ft³ - Fill level: 80% of volume 3. **Formula used:** Weight of water = Volume of water $\times$ Weight per unit volume 4. **Calculate the volume of water when filled to 80%:** $$ V_{water} = 0.8 \times 66 = 52.8 \text{ ft}^3 $$ 5. **Calculate the weight of water at 80% volume:** $$ W = 52.8 \times 62.4 = 3294.72 \text{ pounds} $$ 6. **Compare with maximum weight limit:** $$ 3294.72 < 5000 $$ 7. **Conclusion:** Filling the water tower to 80% of its volume results in a water weight of approximately 3294.72 pounds, which is less than the maximum allowed 5,000 pounds. Therefore, the water tower can be safely filled to 80% without exceeding the weight limit.