Problem
1. Write a function to increase the volume for all the positive values and decrease the volume for all the negative values. Can you still understand any words in the sound?
2. Write a function to set all the negative values of a sound to zero. Can you still understand any words in the sound?
3. Write a function to find the smallest value in a sound and print it out.
4. Write a function to count the number of times the value of a sample is 0 and print out the total.