An onion cell scale is calibrated using a stage micrometer. 100 eyepiece units equal 0.25 mm. A cell is 8 eyepiece units long. What is its length?
Answer and explanation
Correct answer: B. 20 micrometres
- Step 1: One eyepiece unit . Step 2. Length . Answer: 20 micrometres. Why not the others: 2 micrometres and 200 micrometres are decimal-point slips; 32 micrometres divides 8 by 0.25.
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