In an experiment, the weight of several oranges were recorded in the table below. during the experiment, some of the oranges were weighed in grams and some were weighed in kilograms.
find the weights of the oranges weighed in grams in kilograms, and then find the weights of the oranges weighed in kilograms in grams.

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

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%

The mean finish time was 185.52 with a standard deviation of 0.327 minute. the winning car driven by chris finished in 185.13. the previous year race had a mean finish time of 110.3 with a standard deviation of 0.106. the winning car that year driven by karen finished in 110.13 minutes. find their respective z-scores. chris - z-score karen “- z-score