Answer:
B. 50 times greater
Explanation:
Given;
size of phytoplankton = 2 × 10⁻⁶ in
size of sand grain = 1 × 10⁻⁴ in
Determine how many times longer the grain of sand is than the phytoplankton.
Divide the sand size by the phytoplankton size, to find out how much greater the sand is.
This can be done by equating it as follows;
2 × 10⁻⁶ (y) = 1 × 10⁻⁴
Therefore, the grain of sand is 50 times greater than the phytoplankton
B. 50 times greater