Price (P):	$25	$20	$15	$10	$5
Quantity Demanded (QD):	300	600	900	1200	1500
Quantity Supplied 2019 (QS'19):	1500	1200	900	600	300
Quantity Supplied 2020 (QS'20):	800	600	400	200	0

(b) Based on the additional information on expected supply in 2020, use Excel to set up a diagram which shows how the price and quantity of the Christmas trees is likely to change from December 2019 to December 2020.

(c) In the context of your diagram in part b, carefully explains why the price must change. In other words, explain exactly what forces and/or incentives would drive this price change.