6.4
1/2 * 5.4 * 7.1 sin60
Mark brainliest please
Here is how I completed the problem:
I started by creating a ratio:

<em>Where 'x' is the desired amount of the 18% solution of sulfuric acid.
</em>From here, I solved for 'x':
<em>
</em>







∴You will need to add 1080ml of 18% Sulfuric Acid in order to obtain a 15% solution.
If you think about it, 4x7 is half of 8x7 (If you multiply 4, 7, and 2, you get 8x7). So really you can just multiply 4x7 by 2 and you will get 8x7!
5/8- I think that is the right answer