<u>Answer and Step-by-Step explaination:</u>
Area =Length time Width
Area= 21*21
Area=441
Answer:
260 assignments in a school year
Step by Step:
There are 180 days in a school year and you do 3 assignments per day you multiple 180 and 3
The directrix of the parabola is 
<h3>How to determine the equation of the directrix?</h3>
The parabola equation is given as:

A parabola is represented as:

By comparing both equations, we have:
4p = 1/4 ==> p = 1/16
-k= 3 ==> k = -3
The directrix is represented as:
y = k - p
So, we have:

Take the LCM

Evaluate

Hence, the directrix of the parabola is 
Read more about parabola at:
brainly.com/question/1480401
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