Final answer:
To estimate the true mean price with a 90% confidence level, additional statistical data is needed, which the student has not provided. Without the sample mean and standard deviation, it is not possible to calculate a confidence interval and determine the true mean price from the presented options.
Step-by-step explanation:
The student's question is related to the estimation of a true mean price of a graphing calculator using the data from 8 online vendors with a confidence of 90%. This is a statistical problem, and to solve it accurately, additional information such as the sample mean and standard deviation is required, which the student did not provide.
Without this crucial information, it is not possible to calculate a confidence interval and thus estimate the true mean price of the calculator. However, the question presents options for the possible true mean prices, which suggests that the student may be looking for help in understanding how to calculate a confidence interval if the necessary statistical data were available.