Given: ABCD is a quadrilateral, BC║AD, m∠ A = 90°

Prove: BD^2 − AC^2 = AD^2 − BC^2

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Agrain trader buys the following amounts from three suppliers: 3,200 pounds, 5,100 pounds and 700 pounds. what is the total weight of his purchase?

Two language majors, anna and megan, took exams in two languages. anna scored 85 on both exams. megan scored 74 on the first exam and 85 on the second exam. overall, student scores on the first exam had a mean of 82 and a standard deviation of 4, and the second exam scores had a mean of 71 and a standard deviation of 13. a) to qualify for language honors, a major must maintain at least an 85 average across all language courses taken. so far, which of anna and megan qualify? b) which student's overall performance was better?

I’m on question 7 it says a covered water tank is in the shape of a cylinder the tank has a 28 inch diameter and a height of 66 inches to the nearest square inch what is the surface area of the water tank