Answer:
A
Explanation:
Obsessive compulsive disorder is when a person keeps getting compelling repetitive thought.
This case the person might feel the possibility of causing harm to his/herself or others.
The correct answer is D, as business try to have a lower price than their competitors'.
Answer:
Potassium ion
Explanation:
The answer is potassium ion.
The use of flame test is to detect the presence of metal ions in the solution. Different metal ions exhibits different colors when they are put into flames.
Sodium ion when subjected to fire or flame produces yellow flame.
Calcium ions and lithium ions produces red flames.
Potassium ions produces violet or purple flames when put to fire.
The color of the flame of each ion depends on the atomic spectrum of the element.
Thus the answer is Potassium ion.