3) Plutonium-239 has a half-life of 24,000 years and is considered safe only when its radioactivity has dropped to 1% of the original level. Approximately how long must the Pu-239 be stored securely to be considered safe?

Which statement best describes lymph? a. a clear fluid that carries proteins, water, white blood cells, fat, dead cells, and toxins that drain from the fluid between the cells of the body b. a clear fluid in the cells that to secrete and transport hormones from one region of the body to another c. a thick, opaque, and yellowish fluid that is present when there is an infection in the body d. a clear, liquid component of blood that contains red blood cells, white blood cells, platelets, and iron