In the figure is shown a group of 3 charges on an x-y axis at the points: Q1 = 3.06 nC at (x = - L, y = 0) Q2 = Q1 = 3.06 nC at (x = L, y = 0) Q3 at (x = 0, y = 2L) The total electric field of these three charges is zero on the y axis at the point (x = 0, y = d), where d = 0.15 L. (In other words, d is 0.15 times L.) What is the charge Q3? Give your answer in nC to at least three significant digits to avoid being counted off due to rounding. Do not include the units in your answer. 1 nc = 109 C X Q3 y = 2L Q1 Q2 X = -L X= L