Final answer:
To solve Part A, calculate the slope using two given cost-quantity pairs, then determine the y-intercept to form the linear cost equation for iPhone production.
Step-by-step explanation:
The question involves finding linear equations based on given costs and production quantities. Part A requires us to find the equation for the cost of producing iPhones given two cost-quantity pairs. The cost ($C$) of producing $x$ iPhones is a linear function in the form $C = mx + b$, where $m$ is the slope and $b$ is the y-intercept.
We can use the given pairs (100, $102,500) and (2000, $150,000) to solve for $m$ and $b$. The slope $m$ is calculated using the change in cost divided by the change in quantity. The y-intercept $b$ is then found by substituting $m$ and one of the points into the equation.