Zigzag connected transformers are not permitted to be installed on the load side of any system grounding connections.

Explanation:

Zigzag connected transformers are not permitted to be installed on the load side of any system grounding connections is a true statement. When a buck-boost transformer has very little than 9 amperes present, an over current protection mechanism may be valued at not more than 167% of the input current.

i am pretty sure it is c because when people are closer together, they cannot move as freely. picture being in a mostly full elevator, for instance. the people are right next to you, and you can barely move.

because if the tool that you are using is not balanced it there would be false mass.