[Solved] If the elasticity of demand curve for barley is -1.50 at all prices higher than the current price, we would expect that when bad weather reduces the size of the barley crop, total revenue of barley producers will fall. Hypothesized Mean Difference: The presumed difference between the means of two populations or conditions being compared in a statistical hypothesis test. Two-Tail: A term used in statistics referring to the two-tailed test of significance that checks for the possibility of positive or negative differences. Observations: The act of noting and recording something with instruments or the naked eye as part of a scientific or empirical study. Untreated Population: A group in a study or an experiment that does not receive the treatment or intervention being tested.