Hey student is running a 5 km race he runs 1 km every three minutes select the function that describes his distance from the finish line after x minutes

Based on what i know about mean, this doesn't add up.

He weights of 2-pound bags of best dog food are approximately normally distributed with a given mean  and standard deviation  according to the empirical rule, what percentage of the bags will have weights within 3 standard deviations of the mean? 47.5%68%95%99.7%

What is the answer to the question 5x+2x