You could use the information from part A to get B. I'm not sure if you want A or not, so I'll do it as well.
A
Eo = 10^4.4 Joules
E = 2 * 10^15
Formula
M = (2/3) log (E/Eo)
M = 2/3 * log (2 * 10^15/10^(4.4) )
M = 2/3 * log( 7.9621* 10^10)
M = 2/3 * 10.901
M = 7.26735 on the Richter scale. That is a huge amount of energy.
Part B
Suppose that you use Eo and your base. Eo is 10^4.4
Now the new earthquake is E = 10000 * Eo
So what you get now is M = (2/3)* Log(10000 * Eo / Eo )
The Eo's cancel out.
M = 2/3 * log(10000)
M = 2/3 of 4
M = 8/3
M = 2.6667 difference in the Richter Scale Reading. It is still an awful lot of energy.
What this tells you is that if the original reading was (say) 6 then the 10000 times bigger reading would 8.266667
Answer: M = 2.6667
Let
be the random variable for the number of marks a given student receives on the exam.
10% of students obtain more than 75 marks, so

where
follows a standard normal distribution. The critical value for an upper-tail probability of 10% is

where
denotes the CDF of
, and
denotes the inverse CDF. We have

Similarly, because 20% of students obtain less than 40 marks, we have

so that

Then
are such that


and we find

The clear answer according to me would be
5a-8<24
Answer:

Step-by-step explanation:
we have:

we also have:

from (1)(2) => proven
Okay I don’t think I have to do it anymore I