A city map is placed on a coordinate grid. The post office is located at the point
P(5, 35) , the library is located at the point L(15, 10), and the fire station is
located at the point F(9, 25) . What is the ratio of the length of PF to the length of
LF ?
A 2 : 3
B 3 : 2
C 2 : 5
D 3 : 5