What term describes the time it takes for the amount of radioactivity in a material to decrease by one half

Litmus paper is made from water-soluble dyes which are extracted from lichens. this paper is used as an acid-base indicator. which of these common household substances would turn blue litmus paper red? a) bleach b) lye c) soap d) vinegar

Electric charge is what ? a. kinetic energy b. radiation c. discovery d. electricity

Why are people not able to scuba dive in the deep part of the ocean