question 48)
given the following variables
char c = 'c';int i = 10;double d = 10;long l = 1;string s = "hello";
which of the following will compile without error?
1)c=c+i;
2)s+=i;
3)i+=s;
4)c+=s;



question 49)
which of the following will compile without error?
1) file f = new file("/","autoexec.bat");
2) datainputstream d = new datainputstream(system.in);
3) outputstreamwriter o = new outputstreamwriter(system.out);
4) randomaccessfile r = new randomaccessfile("outfile");



question 50)
given the folowing classes which of the following will compile without error?
interface iface{}class cface implements iface{}class base{}public class obref extends base{    public static void main(string argv[]){        obref ob = new obref();        base b = new base();        object o1 = new object();        iface o2 = new cface();    }}
1)o1=o2;
2)b=ob;
3)ob=b;
4)o1=b;




question 51)
given the following code what will be the output?
class valhold{        public int i = 10;}public class obparm{public static void main(string argv[]){        obparm o = new obparm();        o.amethod();        }        public void amethod(){                int i = 99;                valhold v = new valhold();                v.i=30;                another(v,i);                system.out.print( v.i );        }//end of amethod        public void another(valhold v, int i){                i=0;                v.i = 20;                valhold vh = new valhold();                v =  vh;                system.out.print(v.i);        system.out.print(i);        }//end of another}
1) 10030
2) 20030
3) 209930
4) 10020