To increase an amount by 7% what single multiple would you use

Ascuba diver was 80 feet below sea level and swam up at a rate of 4 feet per minute. the two solutions show how long it took the scuba diver to reach an elevation of 20 feet below sea level. lydia and max used the methods shown below to find the time it took the diver to reach the new elevation.

The length of each stair is 11 inches. what is the rise, r, for each stair? round to the nearest inch. 2 inches 7 inches 17 inches 24 inches

The standard deviation for a set of data is 5.5. the mean is 265. what is the margin of error?