Question 315006
in the 70 years between 1920 and 1990, the record decreased .7 sec
___ so it decreased .01 sec per year ___ this is the slope of the line


the intercept is the value in the starting year , 45.5


A.  R(t) = -.01 t + 45.5


B.  just plug in 83 and 86 for t


C.  plug in 44.54 for R(t), and solve for t