A Particular Type of Radioactive Medical Waste Is Shipped to a "Cooling-Down

question 118

Short Answer

A particular type of radioactive medical waste is shipped to a "cooling-down" facility in sealed plastic barrels where it is housed until the radiation intensity falls below a fixed threshold. Upon arrival, a barrel contains 6 pounds of the radioactive material and must be stored until the radioactive component has decayed to 1 pound or less, after which time the barrel may be shipped out for final disposal. If the amount of radioactive waste in a barrel is given by the formula $A = 6 e ^ { - 0.02 t }$ where t is the number of days after arrival, how long must a barrel be stored before it can be shipped for final disposal? Round to the nearest tenth of a day.

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Definitions:

Paranasal Sinuses

Air-filled spaces within the bones around the nose, which help humidify and filter the air we breathe.

Maxillary

Refers to the upper jawbone in vertebrates, which forms part of the skull.

Nasal Conchae

Curved bony structures within the nasal cavity that help to warm, moisten, and filter the air we breathe.

Vomer

A thin, flat bone forming the lower part of the nasal septum, divided by the nostrils.