Which of the following is INCORRECTLY spelled.

The word Mischeif is incorrectly spelled. The correct spelling is Mischief.

Here are the words and their correct spellings:

• Headquarters means the main office or base of operations of an organization.
• Constellation means a group of stars that appear to form a pattern in the sky.
• Mischief means playful or mischievous behavior.
• Receipt means a document that shows that you have paid for something.