Questions

A modem is nothing but short for Modulator and Demodulator. It is used mostly for connecting to the internet.

A modem is a device or program that enables a computer to transmit data over, for example, telephone or cable lines. Computer information is stored digitally, whereas information transmitted over telephone lines is transmitted in the form of analog waves.

#include<stdio.h>

int main(){

  int a[10][10],i,j,sum=0,m,n;

  printf("\nEnter the row and column of matrix: ");
  scanf("%d %d",&m,&n);

  printf("\nEnter the elements of matrix: ");
  for(i=0;i<m;i++)
      for(j=0;j<n;j++)
           scanf("%d",&a[i][j]);
  printf("\nThe matrix is\n");

  for(i=0;i<m;i++){
      printf("\n");
      for(j=0;j<m;j++){
      printf("%d\t",a[i][j]);
      }
 }
 for(i=0;i<m;i++){
     for(j=0;j<n;j++){
          if(i==j)
              sum=sum+a[i][j];
     }
 }
 printf("\n\nSum of the diagonal elements of a matrix is: %d",sum);

 return 0;
}

Sample output:

Enter the row and column of matrix: 3 3
Enter the elements of matrix:
2
3
5
6
7
9
2
6
7
The matrix is
2       3       5
6       7       9
2       6       7
Sum of the diagonal elements of a matrix is: 16

1113122110

In given series 2nd number gives number of  which digits present in the 1st number and so on continues for 3rd ,4th,...

Here 1st no. has only one zero, so  2nd no. is 10 and 2nd no. has one 1 and one 0,so 3rd no. is 1110, so like that 5th no. has one 1,one 3,one 2,two 1's and one 0.So the next no. is 1113122110. 

Uranium is not a fossil fuel whereas coal, petroleum and natural gas are all natural resources.

Fossil fuels are hydrocarbons, primarily coal, fuel oil or natural gas, formed from the remains of dead plants and animals. In common dialogue, the term fossil fuel also includes hydrocarbon-containing natural resources that are not derived from animal or plant sources