b) Is it possible to formulate a conjecture about the units digit of numbers of the form 7^2 -  2^n, where n is a natural number? If so, formulate a conjecture in the form of a conditional statement in the form “If n is a natural number, then : : :

4. Do a direct proof using domain knowledge: An odd integer minus an even integer is odd.

Then after write the converse of the statement

1a) Write 17 x 16 x 15 x 14 x 13 x 12 x 11 x 10 x 9 x 8 in the form „P. 1b) Express 21C, as a sum of two terms from Pascal's Triangle. 1c) How many arrangements are there of the letters in the word ASSOoCIATION? 1d)A club has 25 members. How many ways are there to select a President, Vice-President and Secretary? Assume no one can occupy more than one position. 1e)Which row of Pascal's triangle has a sum of 8,388,608?