Answer:
The smallest possible length is 0.83m
Step-by-step explanation:
Given

Required
The smallest length of the tank
Since the tank is cubical, then the volume is:

This gives:

Express as 


Take cube roots of both sides

Rewrite as:

Approximate

to see quick score she must use a pie chart
You need to measure the angles wich means that u use a protractor if the angle is 90 degrees is a straight angle if it is below 90 degrees is acute and if it is above 90 degrees it's obtuse