Marginal Utility of Commodity with Zero Consumption:
The marginal utility of a commodity when no commodity is consumed is zero. This is because the satisfaction or utility derived from a commodity can only be felt when it is consumed. Therefore, if there is no consumption, there can be no marginal utility.

Consumer's Equilibrium:
Consumer's equilibrium is the point at which a consumer maximizes their utility or satisfaction from the consumption of goods and services. This is achieved when the marginal utility per unit of money spent on each commodity is equal. In other words, the consumer should allocate their income in such a way that the marginal utility per unit of money spent is the same for all the commodities they consume.

Determination of Consumer's Equilibrium:
The consumer's equilibrium can be determined through the following steps:

1. Determine the utility function of the consumer.
2. Determine the budget constraint of the consumer.
3. Determine the marginal utility per unit of money spent on each commodity.
4. Allocate the income in such a way that the marginal utility per unit of money spent is the same for all the commodities.
5. The consumer's equilibrium is achieved when the marginal utility per unit of money spent on each commodity is equal.

Conclusion:
In conclusion, the marginal utility of a commodity when no commodity is consumed is zero. The consumer's equilibrium is achieved when the marginal utility per unit of money spent on each commodity is equal. The consumer's equilibrium can be determined by following the steps mentioned above.