Answer:
A sunflower pollen grain is 0.2 times as large as a ginger pollen grain.
Explanation:
The diameter of a sunflower pollen grain is
meters.
The diameter of a ginger pollen grain is
meters.
We can divide the diameter of the sunflower pollen grain by the diameter of the ginger pollen grain to compare the sizes of these grains.
This gives us:

This means that a sunflower pollen grain is 0.2 times as large as a ginger pollen grain.
So the answer is A sunflower pollen grain is 0.2 times as large as a ginger pollen grain.