Hey any grade 11 physics students here plz help As a chemist CVV Chemicals has asked you to determine the mass of Na2SO4 that it needs to purchase to produce and deliver the required 20kg of sodium sulphide. Calculate the mass of Na2SO4 needed to produce exactly 20kg of sodium sulphide

Karen is running forward at a speed of 9 m/s. she tosses her sweaty headband backward at a speed of 20 m/s. the speed of the headband, to the nearest whole number relative to a stationary observer watching karen

What sort of waves exhibit the doppler effect?

At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.