you're in yr 10?!?!? get outta here!! dont go on blabbering stuff from a book you don't understand. go do physics in year 11 and then you will realise how you just embarrassed yourself.
mate, forget about the 45 degrees thing.
it just a physics question, and can be done with a couple of formulas. That's it, don't get so worked up
to original poster:
DW!! it took me a while to get my head around projectile motion. After these questions it doesnt get much harder ^^