(a)[2]
In how many distinct ways can the $9$ letters of INTELLECT be arranged if the two Ts are adjacent?
(b)[3]
How many distinct arrangements of the $9$ letters in INTELLECT have a T at each end while the two Es are not next to each other?
(c)[4]
Four letters are chosen at random from the $9$ letters in the word INTELLECT. Find the percentage of the possible selections that contain at least one E and exactly one T.