If an exposure time of 60 seconds and source to film distance of 365.7 m (1200 feet) is necessary for a particular exposure, what exposure time would be needed for an equivalent exposure if the source- to-film distance is changed to 457.2 m (1500 feet)?

If an exposure time of 60 seconds and source to film distance of 365.7

1.	If an exposure time of 60 seconds and source to film distance of 365.7 m (1200 feet) is necessary for a particular exposure, what exposure time would be needed for an equivalent exposure if the source- to-film distance is changed to 457.2 m (1500 feet)?
A.	75 seconds
B.	94 seconds
C.	48 seconds
D.	38 seconds
Answer» C. 48 seconds