Please help. I'm not good with Mole ratios. I'll give 100 more points on a different, super easy question if you help (like something about spongebob or something). I don't need you to give me the answer, but could you just explain to me how to figure the answer out? Thanks sooo much if you can!

Two friends at different locations want to communicate with each other by sending low energy signals. which of the following methods can they use to communicate? a) produce x-rays using colliding electrons and send them to radios, which capture sound b) send messages using infrared radiation, which travel in the form of waves c) send radio waves through intervening media like radio and television d) produce sound waves using microwaves from heated objects

When a comet collides with earth, it adds material to our planet and causes great damage. therefore, a collision like this is a a. destructive force b. constructive force c. geologic process and event d. constructive and destructive force

What are the spectator ions in 2h+ + so42- + ca2+ + 2r → caso4 + 2h+ + 21?