An operations manager is calculating the projected growth of a service center's daily calls, which follows an arithmetic sequence. Match each component of the problem-solving process with its correct definition or purpose based on the standard method for finding the first term and common difference when given two terms.

As an inventory manager, you observe that a specific product's stock decreases by a constant amount each week, forming an arithmetic sequence. You have the stock records for Week 5 and Week 11, but the initial stock and the exact weekly decrease are missing. Arrange the mathematical steps from memory to determine the first term ($a_1$) and the common difference ($d$).

A manufacturing supervisor is tracking the ramp-up of a new production line. The daily output follows an arithmetic sequence. On Day 5, the output was 400 units, and on Day 13, the output was 1040 units. Which of the following systems of equations correctly represents the substitution of these values into the formula $a_n = a_1 + (n - 1)d$ to find the initial output ($a_1$) and the daily increase ($d$)?

A warehouse supervisor is tracking the number of shipments processed each day, which follows an arithmetic sequence. On Day 4, the warehouse processed 15 shipments, and on Day 9, it processed 30 shipments. To determine the initial shipments ($a_1$) and the daily increase ($d$), the supervisor substitutes the values for Day 9 ($n = 9$) into the general term formula $a_n = a_1 + (n - 1)d$. In the simplified equation ${}30 = a_1 + k d$, the value of the coefficient $k$ is ____.

In a professional growth model where monthly sales follow an arithmetic sequence, if a manager knows the sales figures for Month 4 and Month 10 but does not know the initial sales ($a_1$) or the monthly growth ($d$), they can determine both values by substituting the known data into the general term formula $a_n = a_1 + (n - 1)d$ to create and solve a system of two linear equations.