There are many dozens of comets, most are small and not very visible.
Generally, a comet has a single tail. However, one recent comet had "split" tails, and historical reports include other sightings of two-tailed comets.
An asteroid
Hard. If you want more specific than that, you're going to need to know about the mass and speed of the comet.
No, Halley's comet is smaller than the Moon
A super comet is a theoretical concept referring to a comet that would have an unusually large nucleus and/or a highly elliptical orbit that brings it close to the Sun. These super comets could potentially be much larger and more spectacular than typical comets. However, no super comet has been observed to date.
It's "Hally's" comet, and no, there are thousands, perhaps millions more
A comet with a period of 200 years or more.
Yes, comets orbit the sun, but usually in an eliptical (oval) or eccentric orbit rather than a more-or-less circular one like the planets.
Depends on the comet. Size varies. But they are usually smaller.
actually a comet will make a bigger tsunami than an earth quake because it depends on how big the comet is so obviously if its a mini comet about the size of a fist its not going to do any affect but a comet like the size of Texas it would make a Mega Tsunami and once there was a Mega Tsunami the size of a city! and it flooded it completely.
No. A light year is the distance light travels in a year, and nothing can travel faster than light. Therefore, the quickest that anything could travel a light year is 1 year. A comet travels much slower than light.
When a comet nears the sun, and begins to out-gas, solar wind pushes the particles away. as the comet nears the sun, more & more particles are emitted, and the tail grows.