If you heat a piece of iron, it will turn red. If you continue heating the iron, it will turn blue. Explain why this happens.

What does earth’s rotation on its axis cause? the tides night and day passing of years phases of the moon

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange