1. **State the problem:** Find the volume of a cylinder given radius $r=5$ mm and height $h=25.5$ mm. 2. **Formula for volume of a cylinder:** $$V=\pi r^2 h$$ This formula calculates the volume by multiplying the area of the circular base ($\pi r^2$) by the height $h$. 3. **Calculate the volume in terms of $\pi$:** $$V=\pi \times 5^2 \times 25.5=\pi \times 25 \times 25.5=637.5\pi$$ 4. **Calculate the numerical value:** Using $\pi \approx 3.1416$, $$V \approx 637.5 \times 3.1416=2001.8$$ 5. **Answer:** The volume of the cylinder is $637.5\pi$ cubic millimeters or approximately $2001.8$ cubic millimeters. 6. **Additional question:** A cylindrical basket has volume $V$ cubic feet and height $h=1.5$ feet. To find the area of the base $A$, use $$A=\frac{V}{h}$$ 7. **Summary:** - Volume formula: $V=\pi r^2 h$ - Base area formula: $A=\pi r^2=\frac{V}{h}$