package rocks.zipcode.calcskin; public class CalcEngine { CalcEngine() { } public double add(double v, double v1) { return v + v1 ; } public double subtract(double v, double v1) { return v - v1; } public double multiply(double v, double v1) { return v * v1; } public double divide(double v, double v1) { return v / v1; } public double square(double v){ return v*v;} public double sqrt(double v){ return Math.sqrt(v);} public double inverse(double v){ double inv = (double)1/v; return inv; } }