<span>If you hold your breath, <span>carbon dioxide </span></span><span>builds up in your blood
The reason for this is:
When you exhale or breathe out, you exert or let out carbon dioxide. So, if you were to hold your breath, it would build up because it is not being exerted.
Hope this helped you!
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Answer:
B. The Time Machine
Explanation:
The narrator meets the Medical Man at the Linnaean Society in the city. The Medical Man thinks the Time Machine thing was a trick, but he can't figure out how the Time Traveller did it. The narrator goes back the following week for the Time Traveller's weekly dinner party.
