Which is not a common radioactive tracer?
select the correct answer below:
o
technetium-99
cobalt-60
thallium-201
o
iodine-131

Read these sentences from the text. near the equator, the tropics receive the most rain on a consistent basis. as a result, the fresh water falling into the ocean decrease the salinity of the surface water in that region. [. .] . . as the salt content of sea water increases, so does its density. what can you infer about how rain affects the density of surface water near the equator?

Frictional forces acting on an object are often converted into energy, which causes the temperature of the object to rise slightly.

Which of the following signs of a chemical reaction are observed in the reaction of potassium with water? precipitate formed temperature change smell produced gas produced color change