Answer:
D. Autonomous expenditures would decrease by 7 units
Step-by-step explanation:
The interest rate affects two components of the autonomous expenditure: consumption and investment. (Look for the equations that has the variable r on it)
In the consumption the impact of one percent increase is calculated as follows:
C = 500 +0.8(Y-T) - 300(r+1%)
C= 500 +0.8(Y-T) - 300r - 300 * 1%
C= 500 +0.8(Y-T) - 300r - 300 * 1%
C= 500 +0.8(Y-T) - 300r - 3 ----> -3 units is the impact over consumption.
Now, let´s analyze the impact on investment.
Ip = 200 - 400r
Ip = 200 - 400*(r+1%)
Ip = 200 - 400r - 400*1%
Ip = 200 - 400r - 4 ----> -4 units is the impact over investment
Then, the total effect over autonomous expenditures = -4 + (-3) = -7