Nine of ten children in a family are right handed. right handedness is a dominant trait.?

Yes

Yes.
c. either both parents are heterozygous (posess both alleles), or one is homozygous for left handedness, while the other is heterozygous.
d. yes - it is a matter of probability.
e. either - also a matter of probability.

Edit: Unfortunately Dark flying dragon seems to be misinformed in her claims that handedness is strictly a learned behaviour and not a genetic trait. I would like to point out that scientists have studied this area extensively, and if you do a little research, you will find that specific genes causing left handedness have been isolated. For example:
http://www.geneticsandhealth.com/2007/07/31/gene-for-left-handedness-is-found/
Although she did include a relevant point from Wikipedia about ?Nature vs. Nurture?, in that genetic predisposition can sometimes be overcome by learned behaviours (ie. a child with a left-handed genotype who, was taught to write with his left hand), her claim that all children are born left-handed is strictly false, as are her unfounded claims that genes play no role in the determination of handedness.

yes
c. Rr x Rr (where R is right and r is left - only way to get a left hander)
d. Yes but the frequency is 75% right 25% left
d. Impossible to tell but 3:1 chances of it being right handed.

actually

I have learned that when children first start to write they are left handed. Being right handed is a learned behavior. I have seen numerous children all the same age, and many of them are left handed. when their parent see that they make the child write with their right hand.

There is no real reason why people are right handed.

Parents chose to make thier children right-handed by correcting them when they write or color with thier left hand.


I for one am ambidextrous. So if there was a genotype from parents than that would be what?


The way you write has nothing to do with being inherited from parents. Even if both parents are left-handed. there is only a 1/4 of a chance that the child they have will be left-handed.

also just because parents are right-handed does not mean their chid will be right-handed.

There is a "theory explains right-handed dominance by claiming that since people are mostly right-handed, parental pressure essentially teaches this behavior as normal. In this way, the right-handed dominance continues. This idea assumes that environmental pressures can dominate over a genetic tendency, indicated by the handedness of children being more closely related to their biological parents than to adoptive parents, and the fact that the percentage of left-handed people has remained virtually unchanged"

http://en.wikipedia.org/wiki/Handedness