A20ft by 40ft rectangular swimming pool is surrounded by a walkway of uniform width. if the total area of the walkway is 396 ft squared, how wide is the walkway

For which rational expression is -2 an excluded value of x?

Using two or more complete sentences, describe how you can find a vector parallel to b=-2,3

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.