I need help finishing this code in visual studio code along with the questions $//$ This program illustrates the use of a sentinel in a while loop.

$//$ The user is asked for monthly rainfall totals until a sentinel

$//$ value of $-1$ is entered. Then the total rainfall is displayed.

$//$ PLACE YOUR NAME HERE

#include Exercise $4$: Complete the program above by filling in the code described in the

statements in bold so that it will perform the indicated task.

Exercise $5$: Run the program several times with various input. Record your

results. Are they correct? What happens if you enter $-1$ first? What happens

if you enter only values of $0$ for one or more months? Is there any numeri$-$

cal data that you should not enter?

Exercise $6$: What is the purpose of the following code in the program above?

if $($month $==1)$

cout No data has been entered" $$ endl;