Answer:
sd = 2720-200r
Step-by-step explanation:
we have savings function to be this eqiuaton
Sd = Y - C^d
from the question we have here:
Y = 7000
T = 1600
C^d = 3200+ 0.2(Y-T)- 200r
we put these values in the savings function
Sd = 7000 - [3200 + 0.2(7000-1600)-200r
Sd = 7000 - [3200 + 1400 - 320] -200r
Sd = 7000 - 3200 - 1400 + 320 - 200r
Sd = 2720 - 200r