Rainwater was collected in water collectors at thirty different sites near an industrial basin and the amount of acidity (ph level) was measured. the mean and standard deviation of the values are 4.60 and 1.10 respectively. when the ph meter was recalibrated back at the laboratory, it was found to be in error. the error can be corrected by adding 0.1 ph units to all of the values and then multiply the result by 1.2. find the mean and standard deviation of the corrected ph measurements.

Two polarizers are oriented at 40∘ to each other and plane-polarized light is incident on them. if only 16 percent of the light gets through both of them, what was the initial polarization direction of the incident light?

What are similarities and differences between refraction, reflection, diffraction and absorption?

While studying chemical reactions and conservation of matter, sarah's class conducted a variety of experiments. sarah and her lab partner found the mass of a wax candle and placed the candle in a flask. the students lit the candle and let it burn to completion. all that was left was wax and charred candle wick. per their teacher's instructions, the students found the mass of the products. their data can be seen in the data table. formulate a hypothesis the students could test to explain why the experiment did not support the law of conservation of matter. a) the students could repeat the experiment using different candles; there might have been a flaw in the candle. b) the experiment should be repeatable. the students should run several trials and then take an average of the after mass in each trial. c) the students should have someone in the class check their measurement skills as they repeat the experiment. they may have made an error using the balance. d) the students should burn the candle in a container that has some type of lid so that any gas that is a product of the reaction can be contained and massed. submit