A student calculated the speed of light in an unknown substance to be 3.5 x 108 m/s. How could you tell if you made an error in your calculations?

Imagine you are standing in the antarctic during the southern hemisphere summer. the sky is clear and blue. there are no clouds in the sky. your shadow is cast on the icy ground. what is the color of the shadow?

Give one example to show that when substances are mixed,it may result in a chemical or a physical change depending on the conditions.

When electrons are added to the outermost shell of a carbon atom, it forms--an anion that has a larger anion that has a smaller cation that has a larger cation that has a smaller radius.