A lumber company is making boards that are 2840.0 millimeters tall. If the boards are too long they must be trimmed, and if they are too short they cannot be used. A sample of 3939 boards is made, and it is found that they have a mean of 2838.2 millimeters. Assume the standard deviation is known to be 10.0. Is there evidence at the 0.02 level that the boards are too short and unusable? Step 2 of 5 :   Enter the value of the z test statistic. Round your answer to two decimal places.

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Q: Engineers must consider the breadths of male heads when designing helmets. The company researchers…

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Q: Engineers must consider the breadths of male heads when designing helmets. The company researchers…

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Q: Engineers must consider the breadths of male heads when designing helmets. The company researchers…

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