During the Months of April Through September, the Following Total

During the months of April through September, the following total utility costs were paid at various production volumes: $\begin{array}{c}\begin{array}{l}\\\\\underline{\text { Month }} \\\text { April } \\\text { May } \\\text { June } \\\text { July } \\\text { August } \\\text { September }\end{array}\begin{array}{cc}&\text { Total }\\\text { Total Utility } & \text { Production } \\ \underline{\text { Costs} } & \underline{\text { Volume} } \\ \$ 5,000 & 16,000 \text { units } \\7,000 & 26,000 \text { units } \\8,000 & 32,000 \text { units } \\6,000 & 20,000 \text { units } \\4,000 & 12,000 \text { units } \\10,000 & 36,000 \text { units }\end{array}\end{array}$
a. Use the high-low method to calculate the cost formula utility costs.
b. If the production volume were expected to be 22,000 units for the month of November, what amount of total costs would be expected?