The Position of a Model Train, in Feet Along the Railroad

Multiple Choice

The position of a model train, in feet along the railroad track, is given by $s ( t ) = 3.5 t + 3$ after t seconds.
Where is the train after 10 seconds

A) 13 feet
B) 38 feet
C) 16.5 feet
D) 65 feet
E) 35 feet