There is no common denomination under barter exchange to express the exchange ratios

True,

All commodities are not of equal value and there is absence of common measure of value.

Explanation:-

In the Barter system, the goods are exchanged with goods.

For example, A wants to sell its 1 Kg. rice and wants to get one pair of shoes. and B wants to sell 1 litre of milk and wants to purchase 1 chair.

In the barter system, each commodity will be compared with all commodities in terms of commodity.

A seller of rice would make a list of how much rice is equal to shoes, chairs, milk, etc.

A seller of shoes would make a list of how much shoes are equal to rice, chair, milk, etc.

Thus, the barter system lacks a common unit to measure all available commodities.