A fair price:

a$.$

is when all sellers of equal goods or services receive the same per unit price.

b$.$

is based on market conditions, and cost structure has no bearing on the determination of a fair price.

c$.$

is based on the cost to produce an item or service without consideration for the supplier$$s profit margin.

d$.$

is the lowest price that ensures a continuous supply of the proper quality where and when needed and at which the supplier makes a reasonable profit.