Cuántas cadenas de ADN diferentes de 20 nucleótidos se pueden construir con las cuatro bases nitrogenadas?

Which two criteria must be met before scientist can use radiocarbon dating? explain your answer

Which short-term environmental changes would a very small asteroid or comet impact on earth most likely cause? check all that apply. flooding extinction craters on surface changes in weather patterns death of organisms and populations

Autonomous underwater explorers will be used to gather large-scale ocean information select the best answer from the choices provided ot