Explanation:
Given that,
A person walks 9.0 km directly east and then turns left and heads directly north for 12.0 km.
We need to find his displacement from the starting position.
We know that,
Displacement = shortest path covered

For direction,

Hence, this is the required solution.
Answer:
ethical dilemmas or ethical paradox
Explanation:
Ethical dilemmas or ethical paradox or moral dilemma is a situation in which a difficult choice has to be made between two or more courses of action, either because the right course of action is not clear or because the right course of action carries some negative consequences. one example is selling a bad product so as not to loose your cost.
Answer:

Explanation:
Assuming that the pacific plate moved 178 km in 1.76 million years.
s = Distance = 178 km
t = Time taken = 1.76 million years
Speed is given by

The speed of the plate is 
Answer:
Valence electrons
Explanation:
The valence electrons are found in the outermost shell of an atom. They are the most loosely held electrons found within an atom. These valence electrons are involved and are used to form bonds when atoms combines together.
The energy required to remove these loosely held electrons is relatively low compared to electrons located in the inner orbitals. This is why when atoms combines, they use the outermost electrons to form bonds and mimic stable atoms like those of the noble gases.