Questions

Acid which is present in vinegar is approximately 5 % of acetic acid. This can be confirmed by testing the vinegar with magnesium which gives out hydrogen as a gas.

#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

'Rare earth'(They are all metals)

Ram Nath Kovind, the present President of India is from BJP, Bharatiya Janata Party.

The president of the Republic India is the head of state of India. He is also the commander-in-chief of Indian Armed Forces. He is indirectly elected by the people through members of both houses of the parliament of India, legislative assemblies of all the states of India, the legislative assembly of the Union

There are about 1,000,000 nephrons in each human kidney.

Nephron, functional unit of the kidney, the structure that actually produces urine in the process of removing waste and excess substances from the blood.