Propose 2 reasons why anthracite coal makes up such a small portion of coal that is mined, even though it is the cleanest and most energy rich form

Which experiment would most likely contain experimental bias

Next pretest: evolution select the correct answer in a laboratory population of flies, the female flies are gray and the males are yellowish gray. biologists observed that all the male flies had an equal chance for reproduction, but the male flies with the brightest colors were more likely to successfully reproduce. what phenomenon could explain such a change? a sexual selection b. disruptive selection c. stabilizing selection d. directional selection

Blood has traveled from the heart to the toes. which describes the next step of the circulation process?