P和Q是两个长方体容器。起初，容器P中水的高度为18.5 cm，而容器Q中水的高度为2 cm。容器P中水的体积为1480 cm^3。

1. Calculate the base area of container P using its volume and height

$\text{Base Area} = \frac{\text{Volume}}{\text{Height}} = \frac{1480}{18.5} = 80\text{ cm}^2$

1. Find the base area of container P (from part a)

Base area of P $= 1480 \div 18.5 = 80 \text{ cm}^2$

2. Find the base area of container Q

Base area of Q $= 40 \times 9 = 360 \text{ cm}^2$

3. Find the total volume of water in both containers

Initial volume in Q $= 360 \times 2 = 720 \text{ cm}^3$
Total volume $= 1480 + 720 = 2200 \text{ cm}^3$

4. Find the new common height

Total base area $= 80 + 360 = 440 \text{ cm}^2$
New height $= \frac{\text{Total volume}}{\text{Total base area}} = \frac{2200}{440} = 5 \text{ cm}$