400
Correct this sentence, if it needs to be corrected. Explain why.
Yes, you included a self-addressed envelope with your order, but unfortunately your order is over-due.
The sentence should read:
"Yes, you included a self-addressed envelope with your order, but unfortunately your order is over due."
The hyphen in "self-addressed" should stay, because it's a compound adjective that needs a hyphen, and the adjective is before the noun that it is modifying.
The hyphen in "over-due" should be removed to make it "over due" because the adjective is after the noun.