Interpreting scale in electron micrographs Steps:

• Locate the scale bar marked as 1 μm in the micrograph.
• Measure the cell's diameter relative to the scale bar; it spans 50 scale bar lengths.
• Calculate: 50 × 1 μm = 50 μm.
• Express as 5 × 10¹ μm. Why C is correct:
• 5 × 10 μm equals 50 μm, matching the measured cell diameter using the 1 μm scale bar. Why the others are wrong:
• A: Meters unit is incorrect; 5 × 10 m is enormous compared to cellular scale.
• B: Millimeters unit is too large; 5 × 10 mm equals 50 mm, not microscopic.
• D: Meters unit mismatches; identical issue to A but possibly different exponent.

Final answer: C