Complete the table below.
High Temperatures $\left({ }^{\circ} \mathrm{F}\right) \quad$ (Round to the nearest hundredth as needed.)
\begin{tabular}{|l|c|c|c|c|}
\hline Class & Frequency, $\mathrm{f}$ & Midpoint & \begin{tabular}{l}
Relative \\
frequency
\end{tabular} & \begin{tabular}{l}
Cumulative \\
frequency
\end{tabular} \\
\hline $18-28$ & 17 & 23 & 0.05 & 17 \\
\hline $29-39$ & 42 & 34 & 0.12 & 59 \\
\hline $40-50$ & 68 & 45.0 & 0.19 & 127 \\
$51-61$ & 69 & $\square$ & $\square$ & $\square$ \\
\hline
\end{tabular}

Step 1 ：Calculate the midpoint for the class 51-61 by taking the average of the lower and upper bounds of the class. This gives us \(\frac{51+61}{2} = 56.0\).

Step 2 ：Calculate the relative frequency for the class 51-61 by dividing the frequency of the class by the total frequency of all classes. This gives us \(\frac{69}{196} = 0.3520408163265306\). Round this to the nearest hundredth to get 0.35.

Step 3 ：Calculate the cumulative frequency for the class 51-61 by adding the frequencies of the current class and all previous classes. This gives us \(17 + 42 + 68 + 69 = 196\).

Step 4 ：The midpoint for the class 51-61 is \(\boxed{56.0}\), the relative frequency is \(\boxed{0.35}\), and the cumulative frequency is \(\boxed{196}\).