Answer:
54%
Explanation:
We are given that
S.D=4.2 lb
Mean=
We have to find the percentage of household throw out at least 9 lb of paper a week.
Normal distribution formula :

We have a=9


%
Hence, the percentage of household throw out at least of paper a week=54%
The answer is A i just took the test.
Complete Question
An isolated charged soap bubble of radius R0 = 7.45 cm is at a potential of V0=307.0 volts. V0=307.0 volts. If the bubble shrinks to a radius that is 19.0%19.0% of the initial radius, by how much does its electrostatic potential energy ????U change? Assume that the charge on the bubble is spread evenly over the surface, and that the total charge on the bubble r
Answer:
The difference is 
Explanation:
From the question we are told that
The radius of the soap bubble is 
The potential of the soap bubble is 
The new radius of the soap bubble is 
The initial electric potential is mathematically represented as
The final electric potential is mathematically represented as
The initial potential is mathematically represented as

The final potential is mathematically represented as

Now

substituting values

=> 
So
Therefore
where k is the coulomb's constant with value 
substituting values

I'm pretty sure its simple! I hope this helps
Answer: a. 5.115 b. 2pi c. i dont know
Explanation: