Explain the role Charles Darwin played in developing the theory of natural selection. (1 paragraph needed)

What evidence did mendel find that supported his law of independent assortment? a. dominant traits are expressed when there is a dominant allele. b. traits do not affect the inheritance of other traits. c. some traits have three or four different alleles. d. plants and animals can both reproduce sexually.

Sally and sue were investigating the topic of friction in science. they used a small car and a ramp as seen in the picture to test what they were learning. they knew that they slipped easily on waxed floors but not on carpet, so they decided to change the material on the surface of the ramp to see what happened. they planned to use glass, carpet, aluminum foil, and sandpaper and run the car down the ramp over each surface. what would be the best research question to guide the girls' experiment? a) does the amount of surface area affect the friction on the moving car? b) will the car travel fastest on the glass surface? c) how does the angle of the ramp affect the speed of the car? d)do rougher surfaces tend to create more friction than smooth surfaces?

Based on the topographic map of mt. st. helens, what is the contour interval of the volcano about height is 2,950 m?