Dan is filling a swimming pool with water at a constant rate.
The table below shows the depth of the water over time.

How can Dan calculate the depth of the water after 6 hours of filling
A. Multiply 1 by 6 and add $\frac{1}{2}$
B. Multiply $2 \frac{1}{2}$ by 2
C. Multiply $1 \frac{1}{2}$ by 6.
D. Multiply $\frac{1}{2}$ by 6 and add 1.