Answer:
Maureen earned $123.19 doing odd jobs
Step-by-step explanation:
The compound interest formula is given by:

Where A(t) is the amount of money after t years, P is the principal(the initial sum of money), r is the interest rate(as a decimal value), n is the number of times that interest is compounded per unit year and t is the time in years for which the money is invested or borrowed.
In this question:
Compounded quarterly means that 
10 years, so 
9% interest, so 
There is $300.00 in the account, which means that 
How much did Maureen earn doing odd jobs?
This is P.





Maureen earned $123.19 doing odd jobs
Whenever you face the problem that deals with maxima or minima you should keep in mind that minima/maxima of a function is always a point where it's derivative is equal to zero.
To solve your problem we first need to find an equation of net benefits. Net benefits are expressed as a difference between total benefits and total cost. We can denote this function with B(y).
B(y)=b-c
B(y)=100y-18y²
Now that we have a net benefits function we need find it's derivate with respect to y.

Now we must find at which point this function is equal to zero.
0=100-36y
36y=100
y=2.8
Now that we know at which point our function reaches maxima we just plug that number back into our equation for net benefits and we get our answer.
B(2.8)=100(2.8)-18(2.8)²=138.88≈139.
One thing that always helps is to have your function graphed. It will give you a good insight into how your function behaves and allow you to identify minima/maxima points.
Answer:
A and B any atom or group or atoms with a negative charge
Answer:
Step-by-step explanation:
If the spinner has an even number of numbers on it, there will be an equal number of odd and even numbers, meaning that the probability of spinning an odd number is 1 2. This is also the probability of flipping heads on a coin. And so we have: 1 2 × 1 2 × 1 2 = 1 8. If the spinner has an odd number of numbers on it, the probability of spinning an odd number will vary. sorry if this isn't right have a nice day.