The Interest Rates That Banks Charge to Borrow Money Fluctuate $t$

Multiple Choice

The interest rates that banks charge to borrow money fluctuate with the economy. The interest rate charged by a bank in a certain country is given in the table below. Let $t$ represent the year, with $t = 0$ corresponding to 1986 . Use the regression feature of a graphing utility to find a quadratic model of the form $y = a t ^ { 2 } + b t + c$ for the data.
$\begin{array}{|c|c|}\hline \text { Year } & \text { Percent } \\\hline \boldsymbol{t} & \boldsymbol{y} \\\hline 1986 & 12.4 \\\hline 1988 & 9.7 \\\hline 1990 & 7.3 \\\hline 1992 & 6.3 \\\hline 1994 & 9.7 \\\hline 1996 & 11.6 \\\hline\end{array}$

A) $y = - 2.13 t ^ { 2 } + 12.61 t + 0.21$
B) $y = 12.61 t ^ { 2 } + 0.21 t - 2.13$
C) $y = 0.21 t ^ { 2 } - 2.13 t + 12.61$
D) $y = 0.17 t ^ { 2 } - 2.58 t + 10.59$
E) $y = 0.25 t ^ { 2 } - 1.73 t + 14.37$