Rosetta, a pitcher, claims that her pitch speed is not equal to 59 miles per hour, on average. Several of her teammates do not believe her, so she decides to do a hypothesis test, at a 1% significance level, to persuade them. She throws 14 pitches. The mean speed of the sample pitches is 58 miles per hour. Rosetta knows from experience that the standard deviation for her pitch speed is 6 miles per hour.

• H0: =59; Ha: 59
• =0.01 (significance level)

What is the test statistic (z-score) of this one-mean hypothesis test, rounded to two decimal places?