a)When silver nitrate comes in contact with skin, it is reduced to white color metallic silver.In most cases, a black stain appears due to formation of finely divided silver which has black color.

The black color is due to the decomposition of the Ag+ ion into Ag, silver. Silver nitrate will slowly decompose with the silver ion reverting to elemental silver. The microscopic particles of silver are so small that they absorb light instead of reflecting it, and so appear black, instead of silver....

Program to input any number and display number of odd numbers in it;

#include<stdio.h>

#include<stdlib.h>

#include<conio.h>

#include<string.h>

int main() {

int i, number, num1, num2=0, num3, num4 =0, rem, rem1, rem2, rev = 0;

printf("Enter your number ==> ");

scanf("%d", &number);

num1 = number;

while(num1 != 0) {

rem = num1%10;

rem1 = rem%2;

if (rem1 != 0) {

num2 = num2*10 + rem;

}

num1 /= 10;

}

num3 = num2;

while (num2 != 0) {

...

Sigma bond is stronger than Pi bond because of the following reasons:

1. The extent of overlapping in Sigma bond is greater than in Pi bond.
2. The electron density in intermolecular axis is more in Sigma bond than in Pi bond.
3. There is free rotation of atom about Sigma bond but not about Pi bond.

1) That old man is Aksionov.

2) The speaker is asking about the truth of digging an escape hole .

3) The speaker means the prison's wall.