Question

The Air Quality Index, or AQI, measures how polluted the air is in your city and assigns a number based on the quality of the air. Over 100 is “Unhealthy”.

Given the following quadratic regression equation, estimate the number of days the AQI exceeded 100 in the year 1988.

n=1.76t^2-13.32t+41.00

(Let t represent the number of years since 1990. Therefore, t = 0 corresponds to the year 1990. Round to the nearest whole day.)
a.
60 days
b.
75 days
c.
61 days
d.
21 days