Answer:
In 1952, Rosalind Franklin produced an image of DNA that suggested it contained two strands twisted in a double helix with a phosphate backbone and bases inside.
Franklin calculated the diameter of DNA, the distance between strands and bases, the angle of the helix, and the number of bases per coil.
Watson and Crick used this information to build and accurate model of DNA.
Step-by-step explanation:
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