UES50. Assume there is no government or foreign sector. If the multiplier is 4, a 20 b i l l i o n i n c r e a s e i n i n v e s t m e n t w i l l c a u s e a g g r e g a t e o u t p u t t o i n c r e a s e b y a . 40 billion. b. 80 b i l l i o n . c . 20 billion. d. $5 billion