To learn the properties of logarithms and how to manipulate them when solving sound problems.
the intensity of sound is the power of the sound waves divided by the area on which they are incident. intensity is measured in watts per square meter, or \rm w/m^2.

the human ear can detect a remarkable range of sound intensities. the quietest sound that we can hear has an intensity of 10^{-12}\; \rm w/m^2, and we begin to feel pain when the intensity reaches 1 \rm w/m^2 . since the intensities that matter to people in everyday life cover a range of 12 orders of magnitude, intensities are usually converted to a logarithmic scale called the sound intensity level beta, which is measured in decibels (\rm db). for a given sound intensity i, beta is found from the equation

\beta=(10\; {\rm db})\log\left( \frac {i}{i_0} \right),

where i_0=1.0\times 10^{-12}\; {\rm w/m^2}.

use this technique to find a formula for the intensity i of a sound, in terms of the sound level beta and the reference intensity i_0. there will be a quantity (10 {\rm db}) involved in your calculations. when you enter your answer, leave off the unit \rm db.
express your answer in terms of beta and i_0.

answer: 0.20

explanation: this can only be the answew because all the other measuremnets are not close

it is the second option.

it becomes positively charged by charging it

elly's long hair:

a. if the salon only takes cash, then this isn't the problem. it doesn't matter how much she has in her checking account.   she can't get a haircut until she has the cash.

b. if she has overdraft protection, then there's no problem.   she can go ahead and write a check that her account can't cover, then sometime later, pay the bank some outrageous usury for loaning her a few bucks for a few days, but with beautiful hair.

c. if elly has some principles, and doesn't want to write a bad check, then now she has a problem.   her desire for the new hairstyle is in conflict with her honesty and integrity.

d.   if the bank will not process a check she writes, then even if she had a million $$ in her account, she couldn't use any of it.   the amount she has in her account is not the problem.   and if i may suggest, she might as well close her checking account, and put the money where it'll work for her.   it's not doing her a bit of good in a checking account, since she can't write any checks.

justin can't pay the full balance:

a. he can't even handle the credit limit he has now.   under no circumstances should he ask for a higher limit.

b.   he can ask for the grace period to be extended.   but that's no solution, the bank will almost certainly refuse anyway, and there are much better options.   he knew the rules of his credit card when he started using it.

c.   he definitely should pay the interest on the balance, plus as much of the balance as he can cover at the same time.

d.   he definitely should pay the minimum otherwise they could shut down his card.   he should also pay as much more as he possibly can.   he should also remember the awkward situation he's in, stop buying stuff on credit that he can't afford, and avoid adding any more debt.

i'd say that justin's best best option isn't on this list of choices.   what he has to do:   pay as much as he can at least the minimum payment plus as much more as he can and then avoid adding more debt.