Cristal is 21 years old and in college.  She has been workin…

Cristal is 21 years old and in college.  She has been working at odd jobs to help pay for school during the summer.  In January, during her winter break, she earned $1800 waiting tables.  This summer she returned to the same restaurant and earned another $2000.  How many quarters of coverage has Cristal earned for the current year?