Which of the following is an example of accrued revenue?

Question $30$ options:

$1)$

snow removal services that has been provided and paid on the same day

$2)$

snow removal services that have been paid for three months in advance

$3)$

snow removal services that have been provided but have not been billed or paid

$4)$

an agreement that has been signed for snow removal services for the next three months