I'm sure that's 100% true.
The human foot has two arches, but the chimpanzee foot has only one.
Below are the choices:
<span>a. creating an online chat group for asking questions and posting solutions
b. establishing a standard method for delivering the results to the teacher
c. offering a wide variety of rain gauges for everyone to choose from
d. using a standard unit of measure for the duration of the study
</span>
the answer is D. I hope it helps.