Write the output of the following String method:

String x = "talent";
String y = "matrix";
System.out.println(x.substring(3).concat(y.substring(3)));

Write the Java statement for creating an object named 'sifra' of the class 'Robot', which takes three double parameters.

Consider and give the output of the following program:

class report{
    int a, b;
    report(){
        a = 10;
        b = 15;
    }
    report(int x, int y){
        a = x;
        b = y;
    }
    void print(){
        System.out.println(a * b);
    }
    static void main(){
        report r = new report();
        r.print();
        report p = new report(4, 5);
        p.print();
    }
}

(a) Name one String method which results in positive integer only.

(b) Name one String method which results in a character.