Dunkirk consulting wishes to predict the amount of overhead expense that will be incurred by a consulting contract, to develop more accurate bids for future contracts. dunkirk has the following data on 11 completed contracts, detailing how long the project took to complete and what the exact overhead expense was: project code name project duration (days overhead expense a11 240 $29,579 a12 97 $11,871 a14 255 $34,254 a18 206 $31,928 a22 189 $21,729 b2 222 $123,822 b33 227 $117,475 b23 259 $135,083 b10 298 $150,142 b14 218 $111,374 b7 268 $141,700 using linear regression, develop a regression formula for predicting overhead expense, based on the duration of the project.