### Question:
MathUtils { public static double findDistance(double x1, double y1, double x2, double y2) { return Math.sqrt(Math.pow((x1-x2), 2) + Math.pow(y2-y1, 2)); } private  MathUtils(); static boolean doublesEqual(double d1, double d2); static boolean doublesEqual(double d1, double d2, double comparator); static double average(double[] nums); static double average(Double ... nums); static double findDistance(double x1, double y1, double x2, double y2); static boolean isWithinTolerance(double value, double target, double tolerance); static double findHypotenuse(double leg1, double leg2);  }### Answer:
@Test public void findDistanceTest() { assertEquals(1, MathUtils.findDistance(0, 0, 0, 1), 0.000001); assertEquals(1, MathUtils.findDistance(0, 0, 0, -1), 0.000001); assertEquals(5, MathUtils.findDistance(0, 0, 3, 4), 0.000001); assertEquals(1, MathUtils.findDistance(1, 0, 0, 0), 0.000001); assertEquals(1, MathUtils.findDistance(0, 1, 0, 0), 0.000001); assertEquals(1, MathUtils.findDistance(0, 0, 1, 0), 0.000001); }