Answer : The grain of sand is 50 times greater than the phytoplankton.
Step-by-step explanation :
As we are given that:
Size of phytoplankton = 2 × 10⁻⁶ in
Size of sand grain = 1 × 10⁻⁴ in
Now we have to determine how many times longer the grain of sand is than the phytoplankton.
We are dividing the sand grain size by the phytoplankton size.
This can be done by equating it as follows:
Therefore, the grain of sand is 50 times greater than the phytoplankton.