Three groups measure the boiling point of the same pure liquid. Group A obtains 79.9 °C, 80.0 °C and 80.1 °C; Group B obtains 76 °C, 80 °C and 84 °C; Group C takes only one reading of 80.0 °C. Which analysis best explains the confidence scientists should place in these outcomes?

A researcher reports that a new catalyst speeds up a reaction. Before accepting the claim, other chemists examine the method and repeat the experiment. What does this example show about science?

The image compares repeated concentration measurements made with four instruments. Which instrument's result should be reported with the greatest confidence based on the displayed uncertainty?

In the image, which feature most clearly demonstrates that scientific investigation is a community process rather than the work of one person alone?