Answer:
The final depth of Melissa is 14 meters below the surface
Step-by-step explanation:
In this kind of problems, involving directions, etc, usually one position is the positive direction and the other position is the negative direction.
In our problem, we suppose that the surface is the positivo zero, above the surface is the positive position(positive depth) and below the surface is the negative directions(negative depth).
The problem states that Melissa is 29 meters below the surface. So, her initial position is 29 meters in the negative direction, so it is equal to -29.
Then, the problem states that Melissa rises upward 15 meters. Upward is the positive direction, so she moved to the positive direction. It means that we are going to do -29+15 = -14 meters.
It means that the final depth of Melissa is 14 meters below the surface
1.) First plug in the values for m and A:

--> 
Isolate b: 
b = 1999
So your answer is the first option.
2.) Admission costs $5.25, so even if you don't go on any rides, you will still have to pay $5.25. This means that for this problem, 5.25 will be the b value. If each ride costs $2.50, then this means it is $2.50x for the cost of x rides. The total cost will then be
.
A:b=c:d
7.2:x=1:25. If u see two ratios equal each other, the product of a and d is equal to the product of b and c. This means that (7.2 times 25) is equal to x. This equals 180=x. The actual distance of the trail of 180 km. Hope this helps!
Step-by-step explanation:
Area of Square ABCD = 10m * 10m = 100m².
Let x = volume of saline solution A,
y = volume of saline solution B.
We're going to set up two equations.
Firstly, x + y = 6. That gives us y = 6 – x (1)
Second, 0.1x + 0.05y = 0.08•6,
or 0.1x + 0.05y = 0.48 (2)
Substitute (1) into (2):
0.1x + 0.05(6 – x) = 0.48
0.1x + 0.3 – 0.05x = 0.48
0.05x + 0.3 = 0.48
Subtract 0.3 from both sides:
0.05x = 0.18
x = 3.6
Then y = 6 – 3.6 = 2.4
So we have to use 3.6 litres of solution A and 2.4 litres of solution B.