Which of the following sentences are correct about a switch loop in a C program?

1:	switch is useful when we wish to check the value of variable against a particular set of values.
2:	switch is useful when we wish to check whether a value falls in different ranges.
3:	Compiler implements a jump table for cases used in switch.
4:	It is not necessary to use a break in every switch statement.

#include<stdio.h>
int main()
{
    int i = 10, j = 20;
    if(i = 5) && if(j = 10)
        printf("Have a nice day");
    return 0;
}

#include<stdio.h>
int main()
{
    int x = 10, y = 100%90, i;
    for(i=1; i<10; i++)
    if(x != y);
        printf("x = %d y = %d\n", x, y);
    return 0;
}

#include<stdio.h>
int main()
{
    int i = 0;
    i++;
    if(i <= 5)
    {
        printf("CuriousTab\n");
        exit(0);
        main();
    }
    return 0;
}

#include<stdio.h>
int main()
{
    float d=2.25;
    printf("%e,", d);
    printf("%f,", d);
    printf("%g,", d);
    printf("%lf", d);
    return 0;
}

#include<stdio.h>
int main()
{
    float *p;
    printf("%d\n", sizeof(p));
    return 0;
}

#include<stdio.h>
int main()
{
    float a=0.7;
    if(a < 0.7f)
        printf("C\n");
    else
        printf("C++\n");
    return 0;
}

#include<stdio.h>
int main()
{
    float a=0.7;
    if(a < 0.7)
        printf("C\n");
    else
        printf("C++\n");
    return 0;
}

#include<stdio.h>
#include<math.h>
int main()
{
    printf("%f\n", sqrt(36.0));
    return 0;
}