Radioactive decay of 40k atoms in an igneous rock has resulted in a radio of 25 percent 40k atoms to 75 percent 40ar and 40ca atoms. how many years old is this rock

When the magnetic domains in a material can be aligned, but eventually drift out of alignment, the material is

Match each scenario to the form of energy it represents

Ineed ! using proper grammar, spelling, and punctuation, write at least one 5 sentence paragraph describing 3 ways we use the elements of the electromagnetic spectrum (ems) in our everyday lives.