11a.prepare for shift(5)d?e?s
12a.a geek turns a student in identifying stimulant(9)a?r?n?l?a
23a.through indiscretion appear an ass.something to do with mule?(3,4,4,2,2)??t?n?s?o?t?n?t
24a.kicking one's habit one's habit!(6)??d?s?
19d.great composer's constant offer to hitch-hiker(6)?h????
thanks in advance