Final answer:
The problem seeks to determine when two phone companies charge the same amount for long-distance calls through setting equal two linear cost equations. However, only one company's charging equation is provided, and more information is needed to answer the question fully.
Step-by-step explanation:
The problem involves finding the point at which two phone companies charge the same amount for long-distance calling, implying they have a linear relationship between the minutes of calling and the total charge. The equation provided (C1 = 0.05m + 25) represents the cost C1 in dollars for company one, where 0.05 is the cost per minute and 25 is the initial charge, and m represents the number of minutes.
To find the number of minutes at which two companies charge the same amount, we would set two equations like this equal to each other and solve for m. However, the information provided does not include the charging details of the second company, so we cannot solve Part B without additional information. The provided data seems to associate with parts of probability and budgeting unrelated to the direct question about phone charges, which suggests that there may be a mix-up with the resource materials. Hence, we cannot definitively select options A, B, C, or D without the equation for the second company.