Write an immutable Vector2 class with:

• Two public final instance variables for the two components, x and y.
• A single constructor that takes two double paramters to initialize x and y.
• A toString() method that returns a String representation of a Vector2 that looks like (1, 2).
• A plus method that takes another Vector2 parameter and returns the Vector2 result of adding this Vector2 to the argument Vector2. Vector addition is defined as: $(x_1, y_1) + (x_2, y_2) = (x_1 + x_2, y_1 + y_2)$
• A minus method that takes another Vector2 parameter and returns the Vector2 result of subtracting the argument Vector2 object from this Vector2. Vector subtraction is defined as: $(x_1, y_1) - (x_2, y_2) = (x_1 - x_2, y_1 - y_2)$
• A dot method that takes another Vector2 parameter and returned the double dot product of this Vector2 and the argument Vector2. Dot product is defined as: $(x_1, y_1) \cdot (x_2, y_2) = (x_1 \cdot x_2) + (y_1 \cdot y_2)$