Use the Practice problem $1$: Based on your own internal research at datafast and what your customer repor, your minidisks seen to have a useful lifetime that is approximately normal distributed with a mean of $33,850$ uses and standard deviation of $2,350$ uses. Solve A$,$B$,$C

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$2$: Weekly demand for wood$-$cutting saws at shirley's Variety is normal distributed with a mean of $100$ and standard deviation of $30.$ Every monday, the store purchases enough saws from it's supplier to bring the stock level up to $150$ saws. Solve A$,$B

Solve Pratice problems Questions $4$ and $5,$please with explanation