That's what you call a mystery. I never had an Empoleon so I don't know
serebii.net , search for Empoleon's page and there are all of his learnable moves.
Empoleon can't learn Earthquake by itself. But you can teach the TM Earthquake, which can be found at Wayward Cave.
Empoleon learn's it around the 70
Pokemon learn moves at there time. Empoleon learns Hydro Pump at level 59 because it can!! Because every time you evolve3 a Pokemon its stats get better but the learning of a new move takes longer. So, for example, if you had stopped the evolution of prinplup to empoleon you could have learned hydro pump at lvl 51.
Empoleon is quite hard to use against an electric type. Your best opyion is to raise a Ground Type to usw against the gym, because Electric moves can't hit a ground type
hydro cannon
Prinplup learns the the moves Bide, Bubblebeam, Fury Attack, Brine at level, Wirlpool, Mist, Drill Peck, Hydro Pump. Also don't let your Prinplup evolve until it learns hydro cannon because it's the strongest move empoleon and prinplup can learn and prinplup learns the move at a lower level than empoleon does.
go to the old mans house on route 228 he will teach starter Pokemon powerful moves
The only way Empoleon can learn Ice Beam is to buy the Tm from the Veilstone Game Corner
No, Empoleon cannot learn Ice Fang by any means in Platinum. It can, however, learn Ice Beam, Blizzard, and Avalanche by TM.
Milotic, if it knows some decent ice and water type moves. Empoleon if it doesn't
Yes he/she can