If investment increases by $15 billion and the economy’s MPC is 0.8 the aggregate demand curve will shift A.Leftward by $75 billion at school price level B .Leftward by $30 billion at each price level...

If investment increases by $15 billion and the economy’s MPC is 0.8 the aggregate demand curve will shift A.Leftward by $75 billion at school price level B .Leftward by $30 billion at each price level C. Rightward by $15 billion at each price level D. Rightward by $75 billion at each price level