Well well if he gets paid. $0.95 per ft^3 this equates to:
pay = $0.95 * volume
because the volume is the amount of ft^3
a trench shape would be considered rectangular. The the volume of rectangle is :
volume = length * width * height
so:
v = 2.5 ft * 2 ft * 150 ft
v = 750 ft^3
so:
pay = 0.95 $/ft^3 * 750 ft^3
p = $712.50