Answer:
The second vector 
points due West with a magnitude of 600N
Explanation:
The original vector 
points with a magnitude of 200N due east, the Resultant vector 
points due west (that's how east/west direction can be interpreted, from east to west) with a magnitude of 400N. If we choose East as the positive direction and West as the negative one, we can write the following vectorial equation:
With the negative sign signifying that the vector points west.
Answer:
The column number tells us the amount of valence electron the element has
Is there a multiple choice?
Given:
The balanced chemical reaction of the synthesis of phosphorus trichloride:
2P + 3Cl2 ===> 2PCl3
Initial amount of phosphorus = 15 grams
The amount of product produced from 15 grams of phosphorus:
15 grams / 31 g/mol * (2/2) = 66.46 grams PCl3
The amount of chlorine is 44.31 grams, nearest to 45 grams.
