As scientists conduct their research, they make observations and collect data. The observations and data often lead them to ask why something is the way it is. Scientists pursue answers to these questions in order to continue with their research.
Answer:
9/20
Step-by-step explanation:
The most common base used today is the decimal system which means 1 to 9.
The binary system is base two and it only uses the numbers 1 and 0. It does not go over 1. So base 5 is a number system that doesn’t go over four. It’s a little hard to understand until you do some questions relating to it.
Y =

You can get this by switching the x and f(x) in the equation and then solve for f(x)
f(x) = 19/2x - 21 ---> now switch them
x = 19/2f(x) - 21 ---> now add 21 to both sides
x + 21 = 19/2f(x) ---> now multiply by 2/19 on both sides
(2x + 42)/19 = f(x) ---> ANSWER
The first one is "unit of account".
The second one is "store of value".
The third one is "medium of exchange".