The correct answer is: [D]: " milk " .
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Choice [A]: "soil" is incorrect; since "soil" is "heterogeneous" {composed of many different "ingredients" .].
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Same with "Choice [B]: "granola" [composed of many different ingredients—clumps of sweetened oats, raisins, coconuts, etc.].
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Same with "Choice [C]: "salad dressing". {Notice how we usually have to "shake the bottle" ? Composed of multiple ingredients, (e.g. oil, vinegar, and spices, or oil and other spices, and more ingredientes).
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Choice: [D]: "milk", as a liquid, is a single, well-mixed, uniform, mixture; as such, it is "homogeneous". Note: "homo-" means "same".
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Answer: A. an electron
<u>Beta particles are electrons or positrons (electrons with positive electric charge or antielectrons).</u> Beta decay is a type of radioactive decay in which a beta ray is emitted from an atomic nucleus.
<u>Beta decay occurs when, in an unstable nucleus with too many protons or too many neutrons, one of the protons or neutrons transforms into the other.</u> In beta minus decay, a neutron is broken down into a proton, an electron, and an antineutrino (the neutrino antiparticle, meaning it has an opposite charge to the neutrino). In beta decay plus, a prototype breaks down into a neutron, a positron and a neutrino.
<span>a. Tall prarie grass burns after being struck by lightning.</span>
A lone oxygen atom has 6 electrons in its outer shell which is not very stable, whereas as full octet (8 outer shell electrons) is stable. In order to achieve this two oxygen atoms will share 4 electrons, each contributing 2 electrons. Since these electrons exist within the orbitals of both atoms, to oxygen atoms essentially achieve a full octet.
The cyanide is

A carbon atom has 4 valance electrons and nitrogen has 5. Below is a Lewis-dot-structure of cyanide.
:N≡C.
The carbon atom is still one electron short of having a full octet and so it will seize another electron from almost anything, making the cyanide ion negative and whatever it took the electron from it now positive.