Mrs. smith's class has been studying properties of minerals in science. she has a mineral sample and wants to know which mineral it is. she performed a scratch test using her fingernail, a copper penny, glass, and a steel nail. which property is mrs. smith testing? a) cleavage b) color c) hardness d) luster

Sarah and john are having a discussion on genetic diversity. sarah believes that it happen over a long period of time. john it happens immediately. who is correct? a. sarah is correct because genetic diversity occurs over a long period of time. b. john is correct because genetic diversity occurs immediately. c. both are correct because genetic variation can occur or long period of time. d. neither are correct because genetic diversity occurs over any period of time