Answer: C. 

Step-by-step explanation:
If 't' represents the number of hours Joanne tutors and 'r' represents the number of hours she works as a receptionist.
Then the total hours she can work=t+r
Since she can work up to 25 hours.
Thus 
If she earns $25 per hour by tuition and $ 12 per hour by working as a receptionist .
Then her total earning =$
Since she must earn $200.
Then
.
Therefore, the required system of inequality will be


The answer to your question is 11.25
When you expand the binomial, you isolate each of the parts.
So, (x-y)^4 would turn into...
x^4 - y^4
The powers stay the same because (outside the parenthesis) you multiply them with whatever is inside the parenthesis. In this case, would be 1. All variables and numbers without a listed power have a power of one. Multiply 4*1 to get 4.
Answer:
8 in
Step-by-step explanation:
RA = 4 in, RB = 2 in
oil height in A = hA = 2 in
Find oil height in B = hB
volume of oil in A = VA = π*RA² * hA
equal amount means volume of oil in B VB = VA
But VB = π*RB² * hB
so π*RA² * hA = π*RB² * hB
then
hB = hA *(RA/RB)² = 2 * (4/2)² = 8 in
Answer:
7
Step-by-step explanation: