Periodically adding, changing and deleting file records is called file updating. The correct answer is A.
<span>The machine should not be oiled until the recommended time between oilings is up.</span>
Line graphs can also be used to compare changes over the same period of time for more than one group. Pie charts are best to use when you are trying to compare parts of a whole. They do not show changes over time. Bar graphs are used to compare things between different groups or to track changes over time.
You will use a <select> for this. For example:
<select name="choice">
<option>First</option>
<option>Second</option>
<option>Third</option>
<option>Fourth</option>
<option>Fifth</option>
</select>
