He graph below shows the velocity f(t) of a runner during a certain time interval:
graph of line going through ordered pairs 0, 4 and 4, 8. graph of another line going through ordered pairs 4, 8 and 8, 0. label on the x axis is time in second and label on the y axis is velocity in meter per second
which of the following describes the intercepts on the graph?
the initial velocity of the runner was 4 m/s, and the runner stopped after 8 seconds.
the initial velocity of the runner was 8 m/s, and the runner stopped after 4 seconds.
the initial acceleration of the runner was 4 m/s2,

Answer is "the initial velocity of the runner was 4 m/s, and the runner stopped after 8 seconds".

This is a velocity - time graph. 

At t = 0 s, the graph has a velocity as 4 m/s. This means, the runner has an initial velocity as 4 m/s. 

At t = 4 s, the runner has reached his maximum velocity as 8 m/s and acceleration is 1 m/s².

After t = 4 s, the velocity has decreased with the time means it is a negative acceleration. 

At t = 8 s, the velocity of the runner has reached to zero means runner has stopped after 8 seconds.

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