this is discrete math combination and permutation could you please answer those question

. In how many ways can 12 people be divided in two teams of 6 for a game of hockey ? If there are two brothers among the 12 people, in how many ways can we divide the 12 people in two teams such that the brothers are on the same team ? . How many permutations of the lettters (1,6, c, d, e, f, g are there ? How many such permu- tations do not contain the pattern abc (as consecutive letters) '2' How many permutations do not contain the patterns abc nor def ? How many permutations do not contain the patterns abc nor cde ? . A coin is tossed 12 times. How many different sequences of heads and tails are possible ? In how many of these sequences are 4 heads ? In how many of these sequences are 4 tails ? In how many of these sequences we get at least 4 tails ? . An urn contains 7 red balls and 7 blue balls. A sample of 4 balls is extracted. HOW many different samples are possible ? How many samples contain exactly one red ball ? How many samples contain at least one red ball ? How many samples contain 2 red balls