Answer: The demand diagram shows an inverse relationship between price and quantity demanded. An increase in consumer income is likely to shift the demand curve to the right. This is because consumers have more disposable income and are therefore willing and able to purchase more apples at each price level.

As a result of this rightward shift, the new equilibrium point will be at a higher price and a higher quantity. The equilibrium price will increase and the equilibrium quantity demanded will also increase. This is illustrated by the new equilibrium point (E2) on the diagram, which lies above and to the right of the original equilibrium point (E1).

• Price: Increases from P1 to P2
• Quantity: Increases from Q1 to Q2

Individual demand refers to the quantity of a good or service that a single consumer is willing and able to buy at different price levels. Market demand, on the other hand, is the total quantity of a good or service that all consumers in the market are willing and able to buy at different price levels.

Market demand is derived from the aggregation of individual demand curves. Essentially, it's the horizontal summation of all the individual demand curves. Therefore, the market demand curve is typically steeper than individual demand curves because it reflects the combined demand of many consumers.

The law of demand applies to both individual and market demand. As the price of a good increases, the quantity demanded by an individual consumer decreases, and similarly, the quantity demanded by the market decreases. Changes in income, tastes, and the prices of related goods can also influence both individual and market demand, although the magnitude of these influences may differ.

Key takeaway: Market demand is the sum of all individual demands, and both are affected by price, income, tastes, and the prices of substitutes and complements.

The demand curve has shifted to the left. This indicates a decrease in demand for mobile phones at every price level.

The most likely reason for this change is a decrease in consumer tastes or preferences for mobile phones. This could be due to a new technology emerging that offers a superior alternative, or a change in social trends that make mobile phones less desirable.

As the demand curve shifts to the left, the equilibrium price and quantity of mobile phones will both decrease. The new equilibrium will occur at a lower price and a lower quantity sold. The exact extent of the change in price and quantity depends on the elasticity of the demand curve.