Sailing

It is the Mermaid class identifier

That depends on where you start & where you intend to arrive. Also the time of year. Also the size of boat. Motor or sail? Intending to move 24/7 or stop to rest?

The mast is the upright mailsail holder. A sprit is a pole that extends diagonally across a fore-and-aft sail from the lower part of the mast to the peak of the sail. Also see bowsprit. All are called sail holders. Tks, Sina.

Irwin 68 Ketch.

Here is the interior plan and sail plan:

http://www.irwinyachts.com/Centercockpitfiles/I68//684.jpg

Simple answer is whenever it is impractical to use the sails. This may because there is no wind, the boat is short-handed, the boat is close to other boats in a marina, or the sails are missing or damaged. The engine offers precise control by only the helmsman, so is usually used in harbor.

Mariners

The Pirates of the Caribbean sail the Caribbean seas, Hence the name Caribbean.

The term "vessel not under command" means a vessel which through some exceptional circumstance is unable to maneuver as required by the Collision Regulations and is therefore unable to keep out of the way of another vessel. Is does not (as often thought) mean (although it can) that there is no one in charge on the bridge.

10 to 14 days dependent on the speed of the ship. From Alaska to Kamchatka (in the summer only) is a few days less.

foremost sail has triangular shape

Landsickness

Kay Cottee

...is called a skiff.

who was the first person to sail around the world

n 1570, Francis Drake, a Devon seaman, sailed to South America and sacked the Spanish town of Nombre de Dios. Later he climbed a tree on the Isthmus of Panama and saw, away in the distance, the shimmer of the Pacific Ocean. He swore that one day he would return and sail an English ship on that great ocean. It was seven years before he achieved this aim. Five ships, led by his flagship, the Pelican, sailed from Plymouth on 8 December 1577. They called at the Cape Verde Islands, then set sail again for the coast of South America. The three largest ships - for the others had been emptied of stores and set adrift - then turned southwards. They reached the Magellan Straits and sailed through to the great expanse of the Pacific Ocean. To celebrate the fact that his dream had come true, Drake decided to change his flagship's name, renaming it the Golden Hind. Alone now, for the other ships had turned back, the Golden Hind began to plunder Spanish settlements on the west coast of South America. Finally, heavy with treasure, the ship turned away from the coast and again headed westwards. On 3 November 1580, nearly three years after leaving England, Drake sighted Plymouth again, having sailed right around the world. He was not only the first Englishman but the very first sea captain to circumnavigate the globe.

16'7".359

A lapper sail is a head sail (jib) that overlaps the mast.

Trapezoidal, actually. But the square sails were called square sails. Lateen or square could be referred to as yards.

A very wide question. In dinghy (small boat) sailing, the RYA method teaches 'five essentials' Sail setting Centreboard Balance (side to side) Trim (fore and aft balance) Course sailed (which is about tacking, allowing for tides etc. Basically, it is about the direction the boat is moving rather than the direction it is pointing) Note that the rudder is not one of the five essentials, it is possible to steer round a course without it.

the shape dose effect it.

Typically wind direction and wind speed. However if you use the technical definition of velocity (speed and direction) then wind velocity and it's acceleration are most important. For example, it's great to know that the wind is blowing at 5 knots NE, but if it's steadily increasing, and veering to the south that's important to know too.

most people think Christopher Columbus did, but he only sailed to the Canaries, Bahamas etc. But it was really Magellan.

About Three thousand B.C.

In a word, flexibility. The are less likely to snap in a sudden high breeze.

Sure...it all depends on the depth of the keel or centerboard (daggerboard). El Toros, for instance, have a relatively short centerboard and can easily sail in shallow water.