(a) Demand and supply shedule
When price = $2, Qd = 30 - 2 =28 Qs = 15 + 2(2) = 19
When price = $4, Qd = 30 - 4 = 26 Qs = 15 + 2(4) = 23
When price = $7 Qd = 30 - 7 = 23 Qs = 15 + 2(7) = 29

Prices ($)	Quantity demanded	Quantity supplied
2	28	19
4	26	23
7	23	29

(b)(i) In equilibrium, Qd = Qs
Therefore, 15 + 2p = 3- -p
2p +p = 30 - 15
3p = 15
p = 5
Equilibrium price is $5.00
Substituting for p = 5, we have
Qd = 30 - 5= 25
OR Qs = 15 + 2(5) = 25
(ii) If price is fixed at $3
Qd = 30 - 3 = 27
Qs = 15 + 2(3) = 21
Excess demand is 27 -21 = 6
(c) If the demand function changes to Qd = 40 - p
(i) When price = $2, Qd = 40 - 2 = 38
When price = $4, Qd = 40 - 4 = 36
When price = $7, Qd = 40 - 7 = 33

Price ($)	Quantity demanded
2	38
4	36
7	33

(ii) It represents an increase in demand
(iii) At the same prices, more quatities of apples are demanded.