An Observer Has Recorded the Following Select $\frac { \bar { t } } { }$

An observer has recorded the following select ( $\frac { \bar { t } } { }$ ) for a five-part task and has applied a rating factor (RF) to each.The times are in seconds.If there is a 15 percent allowance for "nonproductive" activities,compute the standard time for the total task.
$$\begin{array} { | c | c | c | } \hline \text { Element } & \bar { t } & R F \\\hline 1 & 6.2 & 0.9 \\2 & 1.7 & 1.1 \\3 & 4.5 & 1.3 \\4 & 1.2 & 0.8 \\5 & 5.0 & 1.2 \\\hline\end{array}$$
The standard time for the task is

A) fewer than or equal to 21 seconds.
B) greater than 21 seconds but fewer than or equal to 23 seconds.
C) greater than 23 seconds but fewer than or equal to 25 seconds.
D) greater than 25 seconds.