Answer:
b. His t-score is 40.
Explanation:
The middle of the third stanine in a normal distribution means that the standard of nine that is applied has the middle of the third count.
It means that if we divide the normal distribution with the standard of nine we will find the score to be the middle of the third division.
So it will be (1/3*9=3) more than 3.
Which in normal distribution will be more than 30.
The t distribution is approximately normal when the number of degrees of freedom is greater than 30 .
So the best answer is that His t-score is 40 ( choice b).