12 I’m pretty sure because you have x then 3 then 12
The given angles are
M = 64
N = 48
where P is unknown. While we don't know P at first, we can solve for it. Recall that for any triangle, the three angles always add to 180 degrees
M+N+P = 180
64+48+P = 180
112+P = 180
112+P-112 = 180-112
P = 68
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So in summary so far
M = 64
N = 48
P = 68
The shortest side is opposite the smallest angle. The side MP is opposite the smallest angle N = 48
The longest side is going to be opposite the largest angle. In this case, side MN is opposite the largest angle P = 68
The medium side is opposite the medium angle. So NP is the medium side length
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Final Answers:
Shortest Side = MP
Medium Side = NP
Longest Side = MN
See the attached image for a visual summary
The ascending order would be: MP, NP, MN
Note: Something like MP is the same as PM. The order of endpoints for any given individual segment doesn't matter
Answer:

The world population at the beginning of 2019 will be of 7.45 billion people.
Step-by-step explanation:
The world population can be modeled by the following equation.

In which Q(t) is the population in t years after 1980, in billions, Q(0) is the initial population and r is the growth rate.
The world population at the beginning of 1980 was 4.5 billion. Assuming that the population continued to grow at the rate of approximately 1.3%/year.
This means that 
So


What will the world population be at the beginning of 2019 ?
2019 - 1980 = 39. So this is Q(39).


The world population at the beginning of 2019 will be of 7.45 billion people.
The mass should be 75.71 grams
To find density is D = M / V
So you would have to multiply the volume by the density