You are given the following functions that describe aggregate behavior in an open economy:

$C=200+0\mathrm{.}8Yd$

$I=100$

$G=60$

$NT=5+0\mathrm{.}1Y$

$x=40$

$IM=20+0\mathrm{.}2Y$

where C is consumption, I is private investment spending, G is government spending, NT is net taxes $($i$.$e$.$ taxed minus transfers$),$ X is exports and IM is imports.

Calculate expendeture multiplier