Answer
See attached:
Work Step by Step
Using the points given, use a graphing calculator to get the line of best fit or trend line's equation. Press the stat button. Go to edit under the edit menu. Type in the x-values (latitude) into column $L_{1}$ and y-values (temperature) into column $L_{2}$. Press the stat button again. Go to Calc menu and select LinReg(a+bx). Press calculate. You should get $y=-2.49x+137.62$
