While exploring a coal mine, scientists found plant fossils which had been preserved by an earthquake in the ceiling of the mine. Samples taken from one of the fossils had carbon‑14 activities of 20.0 counts / min. A reference sample of the same size from a plant alive today has a carbon-14 activity of 160.0 counts / min. If carbon‑14 has a half-life of 5730 years, what is the age of the plant fossil in years?

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 electromagnetic waves can create ions?

For each of the following compounds, write the formula then predict whether it would be a strong, weak, or non-electrolyte when placed in di water. for the ionic compounds only, put (s) or (aq) after the forrmula formula strong, weak or non electrolyte? a calcium hydroxide b. silver carbonate c. lead(ii) sulfate d. phosphorus trifluoride e. sodium phosphide f barium sulfate g. strontium acetate h. zinc nitrate