Food was cooked, quickly frozen, and then dehydrated in a special vacuum chamber. Freeze-dried food didn't need to be refrigerated and would last a long time. To make most freeze-dried foods, astronauts squeeze water into the food packages and then eat the food after it absorbs the water.
Answer:
Nuclear decay rates are constant
Explanation:
Spontaneous decay of unstable nuclei is a process of a statistical nature, it is not possible to predict with certainty when an individual radioactive nucleus will decay, nor can the decay process be influenced in any way.
Therefore, the half-life of radionuclides (specific for each radionuclide) is defined as the time period in which half of the initial number of radioactive nuclei decays.
The unit of measurement for the radioactivity of the material is the becquerel (Bq) and denotes the number of decays in one second (1Bq = 1 decay / 1 second).
The cell membrane is in control of what materials go in and out of the cell so the correct answer is 4. Regulates diffusion.
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