Which of these describes the use of hieroglyphics and pictographs in ancient times? Select all correct answers. a. They were often drawn on walls
b. They were made using modern art tools
c. They record events and cultural histories
d. They are a form of signal that can be heard.
Explain your answer.

The sun generates both mechanical and electromagnetic waves. which statement about those wave is true?

In a given chemical reaction, the energy of the products is greater than the energy of the reactants. which statement is true for this reaction?

Suppose a wheel with a tire mounted on it is rotating at the constant rate of 2.15 times a second. a tack is stuck in the tire at a distance of 0.373 m from the rotation axis. noting that for every rotation the tack travels one circumference (a) find the tack's tangential speed. (b) what is the tacks radial acceleration?