4. If 175 undecayed nuclei remain from a sample of 2800 nuclei, how many half- lives have passed? (Show your work.) *
Your answer

Hannah is writing a report on how albedo affects the global climate. she’s proofreading her passage for any factual errors. which sentence must hannah correct before submitting her report? earth receives energy from the sun. this energy drives many of the processes on earth, including its climate. some part of this energy is reflected by earth’s surface. we use the term albedo to describe the reflected energy. albedo of an object is the ratio of the reflected radiation to the total radiation reaching the object. a value of 0 means no energy is absorbed by the object, whereas a value of 1 means that all of the energy is absorbed. in this way, the albedo of an object can influence earth’s atmospheric temperature.

Which of the following happens during cell division? (a) energy is created (b) waste is eliminated (c) carbon dioxide is released (d) damaged cells are replaced

Ted and emily played a mixed doubles tennis match against jack and brenda. in the second match. ted and brenda played against jack and emily. which type of chemical reaction does the situation demonstrate?