What do periods and groups have in common as you move through them?

Combustion is the act or process of burning. therefore, i believe the answer is  a: burning wood. 

It's potassium i believe

As long as you're breathing, you'll be fine : /p. s. if you aren't breathing, you'll pass out. mark as brainliest.

Those are different gas lawshere is a brief description of themcharles's law states that volume and temperature are directly proportional to each other as long as pressure is held constant.  boyle's law asserts that pressure and volume are inversely proportional to each other at fixed temperature.gay-lussac's law introduces a direct proportionality between temperature and pressure as long as it is at a constant volume.    source: