What's the first musical instrument? Then Josie sings a song explaining it's the human voice.

Bad Man challenges Sarah and Nico to add numbers with decimals up to the hundredths place. They walk through their process in a manner that is easy to follow and eventually calculate the correct answer. Before they start solving the problem, Bad Man reminds them to estimate so that they can quickly determine if they've gone astray.

Summarizes how critical values and p-values test hypotheses.

Bill introduces the ancestor of the modern clock: the sundial. He illustrates how it uses shadows to indicate the time of day and explains how it influenced the clock. A time lapse then shows how the sundial and clock are in sync as the hours go by during the day.

Shows when and how to use a cumulative frequency plot.