Answer:
Difference = 62.5 micrometer
Explanation:
Given that:
Diameter of red blood cell = 7.5 micrometer
Diameter of coarse grain of sand = 70 micrometers
For calculating the difference between two diameters, we will subtract the diameter of red blood cell from diameter of grain of sand.
Difference = 70 - 7.5
Difference = 62.5 micrometer
Hence,
Difference = 62.5 micrometer