Estimate the cost of forms for 50 concrete beams for a building. The beams are 18 in. wide, 20 in. deep, and 22 ft long. The forms will be used four times. The formwork will be constructed with plywood and dimension lumber. The same material suppliers quotes these prices: $0.55/bf for lumber, $28/sheet for 4ft by 8ft plywood, $0.62/tie for form ties, $0.49/Ib for nails, and $7.50/gal for form oil. Carpenters cost $21.56/hr, foreman cost $28/hr, and helper cost $15.56/hr. Assume foreman is based on 4 carpenters. Use average values from Table. List each step of the calculation. Beam width, in. 12 18 24 Number of uses 1 2 3 4 1 2 3 4 +1234 Plywood, sf 100-110 45-55 35-45 25-35 100-110 50-60 35-45 25-35 100-110 55-65 35-45 25-35 Lumber, bf 260-290 135-150 105-115 90-100 210-235 120-135 100-110 75-85 190-210 100-110 75-85 65-70 Form ties 12 12 12 12 15 15 15 15 20 20 20 20 Labor-hours Carpenter 13.5-14.5 11.5-12.5 9.5-10.5 8.5-9.5 12.5-13.5 10.5-11.5 9.5-10.5 9.0-10.0 11.5-12.5 10.5-11.5 9.5-10.5 9.0-10.0 Helper 3.0-4.0 2.5-3.5 2.0-3.0 1.5-2.5 2.5-3.5 2.0-3.0 1.5-2.5 1.5-2.5 2.5-3.5 2.5-3.0 2.0-2.5 2.0-2.5