Solve the following problems

Explanatoin:

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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%

If x-1 and x+3 are the factors of x3+10x2+ax+b find a and b

Determine domain and range, largest open interval, and intervals which function is continuous.