Which reasons are used to support economists' criticisms of the parity concept?Multiple select question.The relative values of goods and services established by supply and demand stay constant over time.The relative values of goods and services change over time due to a variety of factors.The relative values of goods and services are established by supply and demand.The relative values of goods and services are not based on identifiable factors.

The reasons used to support economists' criticisms of the parity concept are:

1. The relative values of goods and services change over time due to a variety of factors: This is a criticism because the parity concept assumes that the relative values of goods and services remain constant over time. However, in reality, these values can change due to a variety of factors such as changes in technology, consumer preferences, and market competition.

2. The relative values of goods and services are established by supply and demand: This is another criticism because the parity concept does not take into account the forces of supply and demand, which are fundamental in determining the relative values of goods and services in a market economy.

3. The relative values of goods and services are not based on identifiable factors: This is a criticism because the parity concept assumes that the relative values of goods and services are based on identifiable factors. However, in reality, these values can be influenced by a multitude of factors, many of which are not easily identifiable or quantifiable.

The statement "The relative values of goods and services established by supply and demand stay constant over time" is not a criticism, but rather an assumption of the parity concept, which is often criticized by economists.