Please help me understand

60- 0.60 200;60 50 600.50 40- 100,40 PRICE (P=$) 30- $1 500,30 $2 D 20- 0,20 200.20 10 400,10 300.5 0+ 0 100 200 300 400 500 600 700 QUANTITY (Q) 3. Referring to the graph above, which one of the following describes the initial equilibrium price and quantity? (a) P=$5; Q=375 (b) P=$10; Q=350 (c) P=$20; Q=100 (d) P=$40; Q=200