Answer: Second option.
Step-by-step explanation:
Let be "e" the number of easy puzzles Tina solved and "h" the number of hard puzzles Tina solved.
Set up a system of equations:

You can use the Eliminationn Method to solve this system of equations:
- Multiply the first equation by -30.
- Add the equations.
- Solve for "h".
Therefore, through this proccedure, you get:

In the equation, 20 is the original number of fish so we do not change that value to compensate for growth every half year. We will have to change the rate of growth, i.e, 3 and bring 1/2 into its power,
f(x) = 20(3)^(x/2) is correct
Answer:
<em>A stack of 4 trillion one dollar bills will be
meters.</em>
Step-by-step explanation:
The annual expenditure of the US federal government is approximately 4 trillion dollars.
We know, 1 trillion dollars = 10¹² dollars.
So, 4 trillion dollars
dollars.
Each one dollar bill is 0.0001 meters thick.
So, the total height of the stack of 4 trillion one dollar bills will be.....
![[0.0001\times(4\times 10^1^2)]meters\\ \\ =[10^-^4\times(4\times 10^1^2)]meters\\ \\ =(4\times 10^8) meters](https://tex.z-dn.net/?f=%5B0.0001%5Ctimes%284%5Ctimes%2010%5E1%5E2%29%5Dmeters%5C%5C%20%5C%5C%20%3D%5B10%5E-%5E4%5Ctimes%284%5Ctimes%2010%5E1%5E2%29%5Dmeters%5C%5C%20%5C%5C%20%3D%284%5Ctimes%2010%5E8%29%20meters)
19.1 inches. I hope this helps you!