Idon't understand. this is on my homework but it's due tomorrow

(a) (8%) compute the probability of an even integer among the 100 integers 1! , 2! , 3! , until 100! (here n! is n factorial or n*(n-1)*(n-2) *… 1) (b) (16%) compute the probability of an even integer among the 100 integers: 1, 1+2, 1+2+3, 1+2+3+4, …., 1+2+3+… + 99, and 1+2+3+… + 100

Will gve pints stars and brainliest

Dawn is selling her mp3 player for 3 4 of the original price. the original price for the mp3 player was $40. how much is she selling her mp3 player for?