How has submarines changed over the years?

What is the proper procedure for using in Hand held visual distress signal flares? Where do you find the model number on a 1997 Mercury 25 hp Outboard motor? What is the difference in performance between a 200 HP 2 stroke outboard vs a 200 HP 4 stroke outboard? How much is an opti sailboat? Why would water boil in your radiator but the temp gauge is at normal? How much does a 120 force outboard weight? What are the differences between 25 hp and 35hp Johnson outboards? What does the crew do on a cargo ship? What year is your evinrude outboard serial number 5524r-01641? How often should you replace the water pump on a boat? What is a anchor pin? When anchoring at night what light should you display? What are the sampan Boat use for? What is the weight difference between a 15hp mercury motor and a 20hp mercury motor? What do you do if a boat motor catches on fire? What is the fuel to oil ratio for a 1989 70hp Johnson Outboard? What is Un bateau-mouche? What is another name for a log boat? What is the value of USS submarine launching tags? Who owns yacht Triton?