To measure a students retention o knowledge the student is tested after a given amount of time .

To measure a students retention o knowledge the student is tested after a given amount of time . A student score on the hn- pre -clac trst t months after the achool year is over is modeled by s(t)=85-6log base 2 (t+1) where s(t) is the atudent score as a percent . What was the atudent score when the year ended (substitute t=0)