The water level in Ty's swimming pool has a maximum depth of 4 feet. After a day of
swimming with friends, the water level in the
pool drops 6 inches. Which of the following
could best be used to determine d, the depth of
the water in feet, after Ty and his friends went
swimming?
A. d-0.5 is less than or equal to 4
B. d-6 is less than or equal to 4
C. d+ 0.5 is less than or equal to 4
D. d+0.5 is greater than or equal to 4