Pls help I need help on these questions

1mile equals approximately 1.6 kilometers. which best approximates the number of miles in 6 kilometers?

Recall that the owner of a local health food store recently started a new ad campaign to attract more business and wants to know if average daily sales have increased. historically average daily sales were approximately $2,700. the upper bound of the 95% range of likely sample means for this one-sided test is approximately $2,843.44. if the owner took a random sample of forty-five days and found that daily average sales were now $2,984, what can she conclude at the 95% confidence level?

The measures of the legs of a right triangle are 15m and 20m . what is the length of the hypotenuse