Which phrase describes one characteristic of radioactive elements? are produced in a laboratory
decay at a constant rate
have a consistent number of particles
release energy and particles to maintain radioactivity

A hypothesis does not provide an explanation but instead only predicts what may happen.

The explanation given by a theory is well tested and supported by many observations and hypotheses.

Explanation:

Hypothesis is a statement that may be true or false. After that experiments should be performed for testing the hypothesis. If the hypothesis is correct so few more experiments should be done to verify it. If other experiments are also in favor of hypothesis, so it becomes theory. Or if the hypothesis is wrong, another hypothesis be made and experiments are carried out for it.