A rock is thrown in the air from the edge of a seaside cliff. Its height in feet is represented by f(x) = -16(x2 - 6x - 16), where x is the number of seconds
since the rock was thrown. The height of the rock is 0 feet when it hits the
water.
How long does it take the rock to hit the water?
A. 16 seconds
B. 8 seconds
C. 2 seconds
D. 6 seconds

The customer price index(cpi), which measures the cost of a typical package of customer goods,was 208.8 in 2011 and 244.1 in 2016.let x=11 corresponding to the year 2011 an estimate to cpi into 2013 and 2014. assume that the data can be modeled by a straight line and the trend to continue idenfinitely.use data points to find such a line and then estimate the requested quantities