What are the coordinates of the orthocenter of △abc with vertices at a(1, 2) , b(1, 6) , and c(5, 6) ?

Suppose that prices of a gallon of milk at various stores in one town have a mean of $3.71 with a standard deviation of $0.10. using chebyshev's theorem, what is the minimum percentage of stores that sell a gallon of milk for between $3.41 and $4.01? round your answer to one decimal place.