Yes, you can hear a motorboat underwater. Sound travels more efficiently in water than in air, allowing underwater sounds to be transmitted over greater distances. The noise produced by the motor and the vibrations from the boat can be detected by the human ear when submerged, making it possible to hear the motorboat even from a distance.
they hear noises
no
A U-Boat is, in German, ein U-boot, short for "ein Unterwasserboot". That translates to English as "Underwater Boat". "Underwater", of course, translates to Latin as "Submarine".
The length of a motor boat is not restricted
submarine
A submarine.
hydrofoil
Submarine
Motor Boat Cruise ended in 1993.
Motor Boat Cruise was created in 1957.
a under water boat hmm... titanic (kidding) submarine
Making the sound of a motor boat between a woman's breasts. See http://www.urbandictionary.com/define.php?term=motor+boat