Tachycardia is a condition of a heart that beats very fast
Answer:
Here is some background information...
Explanation:
Leeuwenhoek (1633-1723) used melted glass balls to form lenses for apparently crude simple microscopes that nevertheless magnified up to 275 times! Modern tests have concluded that he could have achieved a resolution of two micrometres.
Answer:
C
Explanation:
The helix has to unwind before separating. Once it's separated, then new bases can be added. Once the bases are added, the separate strands wind into helices.
