Question

An agent must know or have available all of the things listed below except _________________?

Answer 1

An agent must know or have available all of the listed criteria to determine if an element is essential or not.

Step-by-step explanation:

All of the following criteria must be met for an element to be regarded as essential:

1. The element is necessary for the growth and survival of the organism. For example, plants require nutrients like nitrogen, phosphorus, and potassium to grow.
2. The element cannot be substituted by another element. For instance, carbon is essential for all living organisms because it forms the backbone of organic molecules.
3. The absence of the element leads to specific physiological or anatomical abnormalities or death. An example is the role of calcium in bone formation; its deficiency can result in weak bones (osteoporosis).

Therefore, the answer to the question is that an agent must know or have available all of the listed criteria to determine if an element is essential or not.