Hannah wants to know which items are attracted to magnets. She decides to conduct an experiment to test a silver crayon, a metal screw, a cotton ball, a bookmark, and a paper clip. Before she investigates, she makes a prediction. She predicts that the silver crayon, the metal screw, and the paper clip will be attracted to the magnet. After conducting her experiment, Hannah finds out that only the metal screw and the paper clip were attracted to the magnet.

What reason MOST LIKELY explains Hannah's prediction that the silver crayon would be attracted to the magnet?
A) The silver crayon is made of iron.
B) The silver crayon is made of nickel.
C) The crayon is silver, which is the color of a metal.
D) She had tried this experiment before using a crayon.

How is mitosis different in plants and animals? a. in animals, the cell membrane pinches together. b. in plants,the dna is one circular chromosomes. c. in plants, there are no sister chromatids. d. in animals, a new cell wall forms.

15 ! come and answer! a(n) is the general term for an infectious disease that has spread across a city, region, or country.

To answer this question, researchers studied populations of the dusky salamander (desmognathus ochrophaeus) living on different mountain ranges in the southern appalachian mountains. the researchers tested the reproductive isolation of pairs of salamander populations by leaving one male and one female together and later checking the females for the presence of sperm. four mating combinations were tested for each pair of populations (a and b)—two within the same population (female a with male a and female b with male b) and two between populations (female a with male b and female b with male a). the proportion of successful matings for each mating combination was measured. for example, when all the matings of a particular combination were successful, the researchers gave it a value of 1; when none of the matings were successful, they gave it a value of 0. then the researchers calculated an index of reproductive isolation that ranged from 0 (no isolation) to 2 (full isolation). the reproductive isolation value for two populations is the sum of the proportion of successful matings of each type within populations (aa + bb) minus the sum of the proportion of successful matings of each type between populations (ab + ba). the table provides data for the geographic distances and reproductive isolation values for 27 pairs of dusky salamander populations.