Maybe you can work it out for yourself:

See image, and suppose we could somehow turn on the mosfet with 12V (this is over the required level, right?) and it would have Rds of .01Ω (Disregard the part #, I'm just pulling these numbers out of the ether!)

What is the voltage from A to Gnd?

What is the voltage from B to Gnd?

What is the voltage from C to B? (This is Vgs)