Which is a correct method used in a scientific experiment involving acid and base solutions? using a ph test strip to measure the oxygen content of a solution adding an indicator to a solution to test its acidity adjusting the recorded ph measurements to prove the hypothesis measuring the ph of a test strip by dipping it into an indicator

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.