A 5-Kg Shark Swimming at 1 M/s Swallows an Absent-Minded

Multiple Choice

A 5-kg shark swimming at 1 m/s swallows an absent-minded 1-kg fish swimming toward it at 4 m/s. The speed of the shark after his meal is

A) 1/2 m/s.
B) 1/5 m/s.
C) 1/6 m/s.
D) 2/3 m/s.
E) 3/2 m/s.