Here we have a system of equation like this:

from the first equation we get:

Substitute in the second equation we get:

Substitute i the first equation again we get:

We deduce that:

A is bigger than B.
Answer:
Mean = 30
standard Deviation = 2.74
Step-by-step explanation:
Formula
mean = np
Standard Deviation = 
from the question = 40
P = 75% or 0.75
q = 1 - p = 1 - 75% or 1 - 0.75
To find mean
mean = 40 x 0.75
= 30
For Standard Deviation (SD)
Standard Deviation =
= 
= 
:. Standard Deviation = 2.74
Okay. 10^12 is 1 trillion. 1 trillion * 7 is 7 trillion. 14 trillion / 7 trillion is 2. The national debt in 2010 is two times larger than in 2003. So that basically means that the national debt doubled from 2003 to 2010.