Answer
0.002% is shown in the microscope.
Work Step by Step
The length of DNA shown is 1.5 um, which is about 4400 nucleotides. $(4400\div1.8*10^8) * 100$ % = 0.002%
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.