9 ducks are swimming in a pond. 4 ducks are white and the rest are black.

What is the ratio of white ducks to black ducks?

The amount of energy it takes to lift a box might be a function of which of the following

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?

32a³b² 8ab² simplify the following expression.