Which childbirth method involves a form of self-hypnosis during delivery that produces a sense of peace and calm which reduces pain?

The lifeguard at the local beach record the tides each day the chart below shows the high and low tides over two days

How were the economies of the northern and southern states different? how ere they the same? what factors led them to develop differently?

For each of the following examples of data, determine which scale of measurement is used. a) the number of miles joggers run per week. b) the starting salaries of graduates of mba programs c) the months in which a firm's employees choose to take their vacations. d) the final letter grades received by students in a math course.