D .All the above.
Explanation:while in the military you can take online courses during service or you can can choose to do it before or after
Answer:
The answer is below
Explanation:
There are cases where the use of a NULL value would be appropriate in a computer programming situation. These cases can be summarily described below:
The first case is in a situation where the value of the attribute of a certain element is known to exist, but the value can not be found
The second case is in a situation where the value of the attribute of a certain element is not known whether it exists or not.