(Question)
Answer the following question given this paragraph: Not every neutron produced by fission induces fission. Some neutrons escape the fissionable material, while others interact with a nucleus without making it fission. We can enhance the number of fissions produced by neutrons by having a large amount of fissionable material. The minimum amount necessary for self-sustained fission of a given nuclide is called its critical mass. Q: The minimum amount necessary for self-sustained fission of a given nuclide is called what? Choices: - its half-life - its molar mass - its activation energy - its critical mass A:
(Answer)
its critical mass

(Question)
Answer the following question given this paragraph: The plasma membrane may have extensions, such as whip-like flagella or brush-like cilia. In single-celled organisms, like those shown in Figure below , the membrane extensions may help the organisms move. In multicellular organisms, the extensions have other functions. For example, the cilia on human lung cells sweep foreign particles and mucus toward the mouth and nose. Q: In single-celled organisms, plasma membrane extensions, such as whip-like flagella or brush-like cilia, aid in what? Choices: - sensation - sound - pressure - movement A:
(Answer)
movement

(Question)
Answer the following question given this paragraph: The female reproductive organs include the vagina, uterus, fallopian tubes, and ovaries ( Figure below ). The breasts are not shown in this figure. They are not considered reproductive organs, even though they are involved in reproduction. They contain mammary glands that give milk to feed a baby. The milk leaves the breast through the nipple when the baby sucks on it. Q: The breasts contain what to give milk to feed a baby? Choices: - sebaceous glands - primordial glands - fetal glands - mammary glands A:
(Answer)
mammary glands