Permutations and combinations. Help pls.?

There are n Straight lines in a plane such that no two of these lines are parallel or no three of them are concurrent. the number of new Straight lines that can be formed out of their intersections is______

(answer is in terms of n)

2. the number of Permutations of the letters of the word PROPORTION taken four at a time is ______

(answer is a number)

3.A and B each throw a pair of dice . The number of ways in which A has a higher Score than B________