TBM Use (days) Tunnel Length (feet) 6 410 15 815 20 1,040 28 1,400 33 1,625 38 1,850 45 2,165 During a construction project, engineers used

 During a construction project, engineers used explosives to excavate 140 feet of tunnel into a mountain. But because of time constraints and environmental concerns, they brought in a tunnel boring machine (TBM) to excavate the rest of the tunnel. The data table lists some observations an engineer made about the length of the tunnel after the TBM was introduced. Which equation represents the length of the completed tunnel based on the number of days since TBM was introduced?                                                                                                       a) y = 45x + 140 b)y = 405x + 140 c)y = 68.33x + 140 d)y = 25x + 140

TBM Use (days) Tunnel Length (feet)   

6                         410

15                       815

20                       1,040

28                      1,400

33                      1,625

38                      1,850

45                      2,165