Expend
to use up (as in energy or money)
Exploit
to use selfishly or for profit
Facilitate
to aid the progress of
Feasibility
the practicality or possibility of something
Ferocity
viciousness, violence
Fiscal
related to (government) money
Flourish
to prosper, grow, or make fast progress
Fluctuate
to be unstable; to rise and fall
Foment
to stir up
Foreseeable
capable of being predicted or anticipated