Which formula can be used to find the magnitude of the
other initial vector, B?

The magnitude of of other vector B can be calculated by

B=

Explanation:

Suppose we have 2 initial vectors A and B. The resultant vector is R

The magnitude of resultant vector will be,

Thus,

B= will be the formula for finding the other initial vector B

                             ⇒  

                             ⇒  

Hence, the correct relation for B will be .

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= initial pressure

= final pressure = 2

= initial volume

= final volume = /4

= initial temperature = 20 c = 20 + 273 = 293 k

= final temperature = ?

using the equation