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Question Pre-1. For a given initial projectile speed vo, calculate what launch angle a gives the longest-range R. Show your work.Question Pre-2. At a fixed launch speed, you observe that the projectile has a certain range R at a launch angle of a = 30. Using this same launch speed, for what other launch angles will the projectile have the same range? Explain. Without using a mathematical formula, give a conceptual argument as to why this angle provides the same range. Question Pre-3. Suppose you measure the range of a projectile for a variety of different launch angles a at a fixed initial velocity vo. You want to plot your data and determine if Equation 3.2 models your data. The easiest way to do this is to plot the range Ron the y-axis versus a quantity on the x-axis that will produce a straight-line plot according to Equation 3.2