How many GB would an 1:30 movie use up on my IPhone 4?

How many GB would an 1:30 movie use up on my IPhone 4?

Added (1). MB and GB if you can.

About 2 to 2.5 gigs

Couldnt you use Wi-Fi? Just warning you, it will be very slow and may buffer a lot if you are on your network data, using Wi-Fi doesn't use up any data and will stop it from buffering.
but you are looking along the lines of about 300 Megabytes.

If you are streaming, it's best to do it on Wi-Fi. If you have the option, just download it an place it on your phone to view at will.