The total should be around $115.27. Here is the breakdown:

USDA APHIS Fee (XA) - $5.00
US Immigration Fee (XY) - $7.00
US Customs Fee (YC) - $5.50
Irish Passenger Charge (UP) - $19.00
Ireland Inspection Pre Clearance Charge (UQ) - $8.90
EI YQ surcharge (YQ) - $24.37
US International Arrival Tax (US) - $17.70
US International Departure Tax (US) - $17.70
US September 11th Security Fee (AY) - $5.60
US Passenger Facility Charge (XF) - $4.50

Business/Economy is the same and for a return trip it's the same whether you start in DUB or BOS.