In this case, the total cost of a student's photography session is dependent on two factors: a standard fee, let's denote it as "sf" for simplicity, and the sets of prints ordered. If we denote the charge for each set of prints ordered as "cps", then, the total cost incurred by a student can be represented as a function of the number of set of prints ordered.
To represent the total cost, we first note the primary components:
1. The standard fee, which is a constant and is not dependent on the number of set of prints ordered. We represented it as "sf".
2. The total cost for sets of prints, which is the product of the number of sets of prints (denoted by "s") and the cost per set (denoted by "cps").
Consequently, combining both components and considering "s" sets have been ordered, we can write the total cost as:
```sf + cps * s```
which is the function rule to represent the total student's total cost.
In this function, "sf" is the constant term and "cps" is the coefficient of the variable "s". The cost per set "cps" directly impacts the term "cps * s".
So, the total cost is a standard fee plus the cost for each set of prints ordered, multiplied by the number of sets ordered.