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Based on the equals method for Circle objects, what is the output for the following code sequence? Circle cl = new Circle(5); Circle c2 = new Circle(5); Circle c3 = new Circle(15); Circle c4 = null; == System out.println(c1 c1); System out.println(cl == c2); == System out.println(cl c3); == System out.println(cl c4); System out.println(c1. equals(c1)); System out.println(c1. equals(c2)); System out.println(c1. equals(c3)); System out.println(c1. equals(c4)); public boolean equals (Circle circle) // Precondition: circle != null // Returns true if the circles have the same radius; // ot her wise, returns false. { if (this.radi us return true; else return false; == circle. radius) }