JNU entrance 2010 58-61 questions

[aswathi]

Y= C+I
I=1000
C= f(Yd)
if Yd = o, then C=500
MPS= 30%
suppose govt. collects a direct tax revenue equal to 15% of Y & makes TR of 750 units of money per year

1. what is d value of investment multiplier in d economy
2. eq. level of Y.
3. If instead of 750 units of money, govt. makes annual TR of 10%, then d value of investment multiplier..

[sara]

ans-1      3.33
ans-2      5000
ans-3      no change.

[sweta]

@ hi sara can u plz explain the answers in steps?
 thx in advance!