Chef Ernie's Sushi-on-a-Stick

Refer to Table 4-5. The equations above describe the demand and supply for Chef Ernie's Sushi-on-a-Stick. What are the equilibrium price and quantity (in thousands) for Chef Ernie's sushi?

Demand Supply 

P = 80 - QD P = 50 + 1/2 QS

QD = 80 - P QS = 2P - 100

A) $40 and 50 thousand
B) $60 and 20 thousand
C) $80 and 80 thousand
D) $50 and 100 thousand

Additional Requirements 
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