總體經濟學問題income vs comsumption (英文) - 經濟

take two points on a straight-line consumption function. when income(Y)
is 100, total consumption (C) is 140. when Y is 200, C is 200

a. Autonomous consumption is 60
b. The component of C that does not depend on income equals 80
c. The component of C that does depend on income equals 60
d. when Y is 200, autonomous consumption equals 1.0

我知道答案..不過整個看不懂...

有哪位大大有時間可以教教我嗎...

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