solve them please:

Investment as a share of Y_ o |/Y_ = 0.18 - 2(R-.04) _ l/Y_ = 0.08 - 2(R-.04) Given the negative shock to investment demand, what value must R be to restore the share of investment to 0.18 or 18%? (Enter as a percent.) Simple version of IS: Y = C + | P C. = Y = a; - b( R - r) Normal times, R = r_= 0.04 High R = 0.06 or 6% Consumption 8 trillion 8 trillion Investment 2 trillion 1 trillion Use this information to estimate the parameter b_. This is a movement along the IS curve. Question : "The value of b_is ? ."