A student said that the sum of the measures of a pair of adjacent angles must equal 180 degrees. Is the student correct?

An automated water dispenser fills packets with one liter of water on average, with a standard deviation of 5 milliliter. the manual says that after a year of operation the dispenser should be tested to see if it needs recalibration. a year later a number of filled packets are set aside and measured separately. it is found that the average packet now contains about 0.995 liters. does the dispenser need calibration? explain your answer.

The measures of the legs of a right triangle are 15m and 20m . what is the length of the hypotenuse

(-y to the power of 2 - 4y- to the power of 2 -6 y +3)