Are these right? i would be sooo grateful if you could take the time

Question 1
What is an object that crashes into Earth called?

Question 2
Which type of comet tail is composed mostly of dust? A(n) ______ tail

Question 3
Which type of tail forms rapidly as the comet approaches the sun? A(n) ______ tail

Question 4
Which type of tail is more curved? A(n)______ tail

Question 5
When is Halley's comet expected to return next? In the year _______ A.D.

Question 6
Comets that appear within every 200 years are called ___________ comets.

Question 7
Which comet has the shortest known period?

Question 8
Comets are invisible until they get near the _______.

I'm not sure about #4 ("head tail"?), but the other answers seem correct to me.

Well, ..., you didn't provide any answers for me to check. I can't do you're homework for you but I'll be more than happy to tel you if an answer is right or wrong.. So please, provide the answers, repost, and I'll tell you which one are right or wrong.

BTW, you can find the answer to most of these by doing a wiki search on comets (http://en.wikipedia.org/wiki/Comet)