(i)[1]
Find how many different arrangements can be formed from the $9$ letters of TOADSTOOL if the three Os stay together and the two Ts stay together.
(ii)[4]
Find how many different arrangements of the $9$ letters in TOADSTOOL have the two Ts separated.
(iii)[2]
Find the probability that a random arrangement of the $9$ letters in TOADSTOOL has a T in the first position and a T in the last position.
(iv)[4]
Choose five letters from the $9$ letters of TOADSTOOL. Find how many different selections are possible if the five letters contain at least $2$ Os and at least $1$ T.