I am currently working on a lab report for my physics class. During the lab, we used air tracks, gliders, and a photogate to measure the value of 'g'. Basically, we would raise one end of the air track to a certain height and let the glider slide down the frictionless track and the timer would go on when the glider entered the photogate and the timer would end when the glider left the photogate. Now, I'm working on the lab report and it wants to know what four averages I would use to find the linear least squares fit. I recorded the original height of the air track, the change in heights, the time it took for the glider to go through the photogate, and the instantaneous velocity when the glider was halfway through the photogate. Can someone help me out and tell me which four values I would need to average to find the least squares fit? I know what to do from there...but I'm having a bit of trouble getting started. Here is more information, just in case: Also, if I wanted to re-arrange this equation: mgh=1/2mv^2, how would I do it so it's a linear equation in the form y=mx+b? I figured I would solve for v^2=2gh...but then what is 'b'?