The half-life of carbon-14 is about 5730 years
Answer:

Explanation:
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In this case, according to the given information, it turns out necessary for us remember that the first-order kinetics is given by:

Whereas the 27.5% complete means A/Ao=0.275, and thus, we solve for the rate constant as follows:

Then, we plug in the variables to obtain:

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Answer
Sounds travel slowest in gasses so it would be air
C. Aluminum (Al) oxidized, zinc (Zn) reduced
<h3>Further explanation</h3>
Given
Metals that undergo oxidation and reduction
Required
A galvanic cell
Solution
The condition for voltaic cells is that they can react spontaneously, indicated by a positive cell potential.

or:
E ° cell = E ° reduction-E ° oxidation
For the reaction to occur spontaneously (so that it E cell is positive), the E° anode must be less than the E°cathode
If we look at the voltaic series:
<em>Li-K-Ba-Ca-Na-Mg-Al-Mn- (H2O) -Zn-Cr-Fe-Cd-Co-Ni-Sn-Pb- (H) -Cu-Hg-Ag-Pt-Au </em>
The standard potential value(E°) from left to right in the voltaic series will be greater, so that the metal undergoing an oxidation reaction (acting as an anode) must be located to the left of the reduced metal (as a cathode)
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From the available answer choices, oxidized Al (anode) and reduced Zn (cathode) are voltaic/galvanic cells.
Adaptation actually and also following control measures on how to avoid it from happening