Which of these is a disadvantage of hydroelectric energy ? a. is expensive to build or maintain b. has high power plant efficiency c. has a long power plant life span d. reduces greenhouse gas emissions

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

Round seeds and yellow seed color are dominant to wrinkled seeds and green seed color. which punnett square represents the correct way to set up the cross rryy  ´  rryy? 

Most animal cell membranes have proteins that pump. ions out of the cell and potassium ions into this