Final answer:
The correct method to label a plane is to use at least two lowercase letters, with the first letter of the second word capitalized. Both words should be italicized.
Step-by-step explanation:
The correct method to label a plane is to use at least two lowercase letters. Both words should be italicized, and the first letter of the second word should be capitalized. For example, if you want to label a plane as 'xy', you would italicize both 'x' and 'y', and capitalize the 'y'.