Freight car loadings over an 18-week period at a busy port are as follows: Week Week Week Number 310 1 7 13 330 8 350 9 330 10 11 12 1234 2 4 56 350 365 Number 405 425 445 425 445 465 t 14 15 16 17 18 Number 480 495 535 555 575 595 a. Determine a linear trend line for expected freight car loadings. Y = b. Use the above trend equation to predict expected loadings for Weeks 20 & 21. c. The manager intends to install new equipment when the volume exceeds 890 loadings per week. Assuming the current trend continues, in which week (at the earliest) should the loading volume reach that level?