Answer:
The time required for a radioactive substance to lose 50 percent of its radioactivity by decay is known as the half-life. Plutonium-238, plutonium-239, and plutonium-240 are isotopes of plutonium, and have half-lives of 87 years for plutonium-238, 24,065 years for plutonium-239, and 6,537 years for plutonium-240.
Step-by-step explanation: