Why don't x-rays, gamma rays, and most uv rays reach earth's surface?

the atmosphere blocks or absorbs them.
they don't have enough energy to travel that far.
the wavelengths are too short to reach earth.
they are destroyed when older stars collapse.

What semimetal can form four single covalent bonds.

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.

*will mark you brainliest + 15 points ** why does the equilibrium of a system shift when the pressure is increased? a. to maximize the stress on the system b. to stop restoring equilibrium to the system c. to increase the total moles of gas in the system d. to decrease the total moles of gas in the system