_A model of torpedo is tested in a towing tank at a velocity of 25 m/sec. The prototype is expected to attain a velocity of 5 m/sec. What model scale has been used?$?

_A model of torpedo is tested in a towing tank at a velocity of 25 m/s

1.	_A model of torpedo is tested in a towing tank at a velocity of 25 m/sec. The prototype is expected to attain a velocity of 5 m/sec. What model scale has been used?$?
A.	1 : 5
B.	1 : 2.5
C.	1 : 25
D.	1 : ?5
Answer» B. 1 : 2.5