1. 10 hr + 39 min = (10 hr x 60 min/1 hr) + 39 min = 600 min + 39 min = 639 min
2. 91 cm/day x 1 in/2.54 cm x 1 day/24 hr = (91 x 1 x 1)/(1 x 2.54 x 24) = 1.49 in/hr
3. 0.04(30h) represents the amount of tax at a tax rate of 4%
