The potassium- nuclide radioactively decays by positron emission. Write a balanced nuclear chemical equation that describes this process.

Your friend offers to show you an intrusive igneous rock. which of the following would you expect to see?

Agroup of students is studying convection current. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other is in an area with warm air. after 10 minutes, the balloon are released from a height of 1 meter. which of the following to the students most likely observe? a) the warm balloon expands and rises. the cold balloon shrinks and sinks b) the balloon both rise. the cold balloon is larger than the warm balloon c) the cold balloon expands and rises. the warm balloon shrinks and sinks d) the balloon rise at the same rate. both balloons are the same size

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?