Final answer:
The ratio of cash to monthly cash expenses is -0.75.
Step-by-step explanation:
To calculate the ratio of cash to monthly cash expenses, you need to divide the cash and cash equivalents by the monthly cash expenses. In this case, the cash and cash equivalents at the end of the year are $540. To find the monthly cash expenses, we need to consider the negative cash flows from operations, which are $(720). So, the ratio would be:
Ratio = Cash and cash equivalents / Monthly cash expenses
Ratio = $540 / $(720) = -0.75
Therefore, the ratio of cash to monthly cash expenses is -0.75.