The Celsius degree is the same size as the Kelvin.
The correct choice is 'C'.
<h3><u>Answer;</u></h3>
= 73 N
<h3><u>Explanation</u>;</h3>
Using the formula
2 T cos(30°) = w
Where; T is the tension on each string, while w is the weight of the box given by mg
Therefore;
W = 2Tcos 30°
= 2 × 42 cos 30°
= 84 cos 30°
= 72.74
<u> ≈ 73 N</u>
When multiple forces are at work on an object, the net force is called a <em>resultant</em>, because it's a sum of vectors, and a sum of vectors is called their resultant.
