Answer: the answer is 7.5
Step-by-step explanation:
Firstly attention should pe paid to the exact words given in the problem and then only the answer can be easily deduced.
It is a 2 digit number and that is said in the problem
Now For the tens digit it has been said that it is 8 more than the ones digit. The ones digit cannot be zero and that is already mentioned in the problem.
So if we take the ones digit to be 1, then the tens digit will be= 8 +1
= 9
Now if we take the ones digit to be 2, then the tens digit will be = 2 + 8
= 10
So it cannot be 2 as the tens digit takes the number to a 3 digit number and it is not possible.
So the answer to this problem is 91.
Hack
for y=ax^2+bx+c
the xvalue of the vertex is -b/2a
and the y value is found by subsituting that for x
so
-b/2a
h(t)=2x^2+4x+7
a=2
b=4
-b/2a=-4/(2*2)=-4/4=-1
the y value
h(-1)=2(-1)^2+4(-1)+7
h(-1)=2(1)-4+7
h(1)=2+3
h(1)=5
(-1,5) is da vertex
30,000 - 19,500 = 10,500 gallons left to fill the pool. So I am assuming the answer would be w = 10,500 gallons... unless there was an equation missing in the question
Answer:
The ratio of the drag coefficients
is approximately 0.0002
Step-by-step explanation:
The given Reynolds number of the model = The Reynolds number of the prototype
The drag coefficient of the model,
= The drag coefficient of the prototype, 
The medium of the test for the model,
= The medium of the test for the prototype, 
The drag force is given as follows;

We have;

Therefore;







= (1/17)^3 ≈ 0.0002
The ratio of the drag coefficients
≈ 0.0002.