Final answer:
To have a coefficient of determination of at least 0.50, a correlation coefficient of 0.71 or higher is necessary.
Step-by-step explanation:
The coefficient of determination is the square of the correlation coefficient, or r². In this case, the student wants a coefficient of determination of at least 0.50. To find the correlation coefficient that would result in this coefficient of determination, we can take the square root of 0.50, which is approximately 0.71. Therefore, a correlation coefficient of 0.71 or higher is necessary to have a coefficient of determination of at least 0.50.