please answer all the questions it is urgent

4. If a tree has four vertices of degree 2, one vertex of degree 3, two vertices of degree 4 and one vertex of degree 5, how many pendant vertices does it have? [4] 5. Place the words in the order in which they appear FOUR SCORE AND SEVEN YEARS AGO OUR FOREFATHERS BROUGHT FORTH, in a binary tree by using the usual dictionary ordering. [41 6. Let a, b e Z. Let ab=qn+s where 0