The following graph shows the approximate value of the U. Consumer Price Index ( CPI ) from September 2004 through November 2005 . | ( t ) [FI Sep...

I(t) = −0.005t3 + 0.12t2 − 0.01t + 190    (0 ≤ t ≤ 14),

t

(a) Use the model to estimate the monthly inflation rate in March 2005 (t = 6). [Recall that the inflation rate is I'(t)/I(t).]

 (Round your answer to three decimal places.)

 %

(b) Was inflation slowing or speeding up in March 2005?

slowing down

speeding up

(c) When was inflation speeding up? When was inflation slowing? HINT [See Example 3.] (Use the model to determine this.)

Inflation was speeding up prior to 

 ---Select--- January February March April May June July August September October November

 2005 and slowing after 

 ---Select--- January February March April May June July August September October November

 2005.

The following graph shows the approximate value of the U. S. Consumer Price Index ( CPI ) from September 2004 through November 2005 .| ( t )[FI Sep 20.04_ Nov 201 15202,200198195194192190188 1O24810 12 14Jan - 175Nov - 215The approximationg curve shown on the figure is given by[ (t ) = - 0. 005+ + 0. 121 - 0. 01t + 190 ( 0 = = = 1 4 ),where I is time in months since the start of September 2004 .( a ) Use the model to estimate the monthly inflation rate in March 2005 ( = = 6 ) . [ Recall that the inflation rate is !' (ty / I(t ) . I ( Round your answer to three decimal places . )( b ) Was inflation slowing or speeding up in March 2005 ?)O' slowing downO speeding Up( C ) When was inflation speeding up ? When was inflation slowing ? HINT [SEE Example 3 . ] ( Use the model to determine this . "Inflation was speeding up prior to| _ _ _ Select _ _ _*$ 2005 and slowing after| _ _ _ Select- - -$ 2005 .