I'm probably not going to get enough right to join but i'll try, since I consider myself at least decently knowledgable on the subject of Pokemon. (I tend to absorb useless trivia rather than useful information)
1.Which is the weakest pokemon?
Not sure exactly, but Magikarp is a strong contender for this
2.How long to you have to wait to make the evolution machine work?
That I don't know, need to clarify that one. I've actually haven't even heard of a proper "evolution machine" so I suspect there might not be such thing as one.
3.What is Prof.Oaks first name?
His first name is Samuel
4.Name the described pokemon.I am pink and cute.I use sing SOMETIMES to put my enemys asleep.Who am I?
Most likely, it is Jigglypuff, but with such a vague description it could also be desribing Clefairy as well
5.Which pokemon is fire and steel?
Heatran I believe (can't spell well)
6.Can a magikarp beat a gyarados?
In the game, if thier levels are the same, its techinally impossible for a Magikarp to beat a Gyarados. The only real way it would be possible is if the level distance was massive enough and I'd need to test this to see if that is possible.
7.Name the pokemon that Dragon/flying and uses Dragon rage.
As Dratini can learn Dragon Rage. I'll go with Dragonite. My knowledge about dragons is very bad through. Note that even it the Dratini line doesn't learn Dragon Rage naturally, it was available as a TM in R/B/Y and with the Dratini line being the only dragon type in that generation, theorically its is correct since you only "uses Dragon Rage". If its a question to do with the anime, i'm not going to know the answer since the land down under is behind the US and Japan and I always seem to miss episotes.
8.Name three pokemon Prof.Oak had and 4 for a bonus.
I only know of one definite. Dragonite
9.How does Latias change into a different form?
Well, I'm just lucky that the OP memtioned something about that when asking to join a certain club, otherwise I wouldn't know. By the use of light. It can refract the light striking it. (If I wasn't in that club, i'd wouldn't have a chance in hell, since I haven't seen many of the movies)
10.What color is shiny mew?
As I'm not one for shinies this I don't know...It would also be cheatoing if I looked it up as well.
BONUS!!!What is different about pokemon rangers than trainers?
If you are referring the the "Pokemon Ranger" rangers and not the trainers found in certain areas of R/S/E and D/P, theres a few differences. The major one i've noted is that despite that they both do capture pokemon, a rangers method of capture is vastly different and only allows to call on the pokemon for either a short period or once. After that the pokemon is free again, while a pokemon captured by a trainer is tied to the capturing device (the pokeball) permanently unless it is broken or if the trainer chooses to release it.
My final analysis: I'll probably score an fail and only get 4 or 5 right.