select 'mode' from command line?

[Gustavo Seabra <gustavo.seabra@gmail.com>]

Hi,

I'm working witha code that has both fortran 77 and fortran 90 parts. All the 
files, however, are named *.f, and emacs always opens them with the 'fortran 
mode', which is actually more fortran77. So, I wonder if there's a way to tell 
emacs to use a specific 'mode' from the command line, overriding the default 
definition. Something like:

 $emacs -f90 my_f90_file.f &

to force emacs to already open the file with the f90 mode.

Thanks,

Gustavo Seabra.