Monthly Reserve / Guarantee

[AndyDRHuddleston]

I have been looking at the salaries of american positions and am slightly confused. If a position advertises say $22 p/hr with 75hrs guaranteed and 75 hrs reserve what would be the monthly pay?

Would it be $22 x 75 ($1650) or $22 x 150 ($3300)?

Also, is per diem paid per flying hour, or per hour on duty?

Thanks

Andy