Final answer:
The assistant can include taxes and inventory expenses in the operating expenses.
Step-by-step explanation:
In an income and expense statement, the assistant can include the operating expenses, which are the costs incurred in the day-to-day operations of the business.
The assistant can include expenses such as taxes and inventory expenses in the operating expenses.
However, the assistant cannot include expenses such as loan payments, cost of land purchase, and cost of heavy machinery purchase in the operating expenses as they are not related to the day-to-day operations of the business.