Express into the fractions with common denominator (11-20): a a у а 11. 11 12.*, 13. 2x By 3m 2n 14. b a - b'a+b bc ac pq pr 15. a x ya a-2ab' a + 2b 3 2 16. a? - 4' a(a + 2) 17. b a² - 9²a+3 a b с 18. a b 19. с a+b a-b' a-c a - b' a+b' a(a + b) 3 20. 2 x -x-2' x + x-6​

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.

Add the two expressions 3.8b - 7 and 2.9b + 9 enter your answer in simplified form

Three baby penguins and their father were sitting on an iceberg 0.50.50, point, 5 meters above the surface of the water. the father dove down 4.74.74, point, 7 meters from the iceberg into the water to catch dinner for his kids. what is the father penguin's position relative to the surface of the water?