slope=rise/run from left to right
rise=-3 becase goes down 3
run=4 because goes 4 units
slope=-3/4
boxes filled per minute is boxes/minute
pick a point, 3 boxes and 4 minutes, so that is 3/4 or 0.75 boxes per minute
anwers are 3 boxes every 4 minutes and 0.75 boxes per minute
that will be the one that passes through the point when time=1 minute, laps=3
looks like line b
slope=rise/run=(5000-3500)/(2-5)=-500
it drops 500m every minute
1st option