2. Plot every 8th data point. What was the average speed of the bicycle in each interval? Connect the data points with line segments. What is the slope of each segment? - The slope of each line segment is the average slope of the bicyclist in each interval.

We take every 8th data point and plot the position data - both unjoined and joined.

Input := 

sdata8 = Table[data[[i]],{i,1, Length[data],8}];

Input := 

ListPlot[sdata8,PlotStyle->{PointSize[.02]},
	PlotRange->{{-5,150},{-50,3000}},
	AxesLabel->{"time [sec]","pos [ft]"}]

Output =

-Graphics-

Input := 

ListPlot[sdata8,PlotStyle->{PointSize[.02]},
	PlotJoined->True,
	PlotRange->{{-5,150},{-50,3000}},
	AxesLabel->{"time [sec]","pos [ft]"}]

Output =

-Graphics-

We compute the average velocity over these time intervals and plot the velocity at the right hand side of each sub-interval.

Input := 

vdata8 = Table[{sdata8[[i+1]][[1]],
	(sdata8[[i+1]][[2]] - sdata8[[i]][[2]])/
	(sdata8[[i+1]][[1]] - sdata8[[i]][[1]])},
	{i,1, Length[sdata8]-1}];

Input := 

ListPlot[vdata8,PlotStyle->{PointSize[.02]},
	AxesLabel->{"time [sec]","vel [ft/sec]"}]

Output =

-Graphics-

Input := 

ListPlot[vdata8,PlotStyle->{PointSize[.02]},
	PlotJoined->True,
	AxesLabel->{"time [sec]","vel [ft/sec]"}]

Output =

-Graphics-