That's the definition of the property called "density".
Answer with Explanation:
We are given that
A=3i-3j m
B=i-4 j m
C=-2i+5j m
a.


Compare with the vector r=xi+yj
We get x=2 and y=-2
Magnitude=
units
By using the formula 
Direction:
By using the formula
Direction of D:
b.E=-A-B+C


units
Direction of E=
Answer:
<h2>23.33 kg </h2>
Explanation:
The mass of the object can be found by using the formula

f is the force
a is the acceleration
From the question we have

We have the final answer as
<h3>23.33 kg</h3>
Hope this helps you
Explanation:
everything can be found in the picture
It's a Angstrom Exponent. You can research that term from here.