Respuesta :

time given 80 s and 100 s

t f= 100 s   v f= 20 m/s

t i= 80 s     v i= 2 m/s  [i think its 2 because its not touching the x-axis so,it cannot be 0]

use the equation now:

A= v f-v i /t f-t i

v f-v i = 20-2 =18 [if u use vi as 0 then its 20 ][ then the answer  is 1]

t f-t i = 100-80 =20

answer is 18/20