Answer:
weakness of core muscle can lead to chronic back pain
Explanation:
Create the column headings "Reactants" and "Products". The two row headings should be "Photosynthesis" and "Cellular respiration".
Before filling in the table, make sure you know what the products and reactants from photosynthesis and cellular respiration are.
Remember reactants are the 'before' on the left, and products are the 'after' on the right.
<u>Photosynthesis</u>:

<u>Cellular Respiration</u>:

See attachment for how the table could look.
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.