Doing this to check my work, Thanks!

QUESTION 30 We study a variable X. We have a sample of size n=620 and we found Y = -86.5, with s -1165.32 (with s being the sample variance). We run the following hypothesis test: Ho : My = - 83.1 H1 : Wx * - 83.1 What is the t-stat of that test? (Round your answer with 4 digits after the decimal.)