The Race Speeds (In Minutes)for the Top Eight Cars in a 200-Mile

Multiple Choice

The race speeds (in minutes) for the top eight cars in a 200-mile race are listed below. Use the range rule of thumb to estimate the standard deviation. Round results to the nearest tenth. $\begin{array}{llllllll}181.0 & 180.6 & 189.2 & 182.2 & 175.6 & 180.0 & 177.9 & 181.8\end{array}$

A) 1.1 minutes
B) 6.8 minutes
C) 7.5 minutes
D) 3.4 minutes