Answer:

Step-by-step explanation:
In 5 liters, there is 4% salt.
Lets find liters of salt.
First, converting 4% to decimal (dividing by 100):
4% = 4/100 = 0.04
0.04 * 5 = 0.2
So, there is 0.2 liters of salt.
Now, x liters of water is added to total, so total is now:
5 + x
The concentration of salt will be amount of salt divided by amount of salt water solution.
Amount of salt = 0.2 (as seen above)
Amount of new salt water solution = x + 5
So,
Concentration of salt in new solution is 
2nd choice is right.
Answer:
1.71
Step-by-step explanation:
x/4 = 3/7
4 * 3 = 12
12/7 = 1.714285714285714
Rounded to the nearest hundreths, the answer is 1.71
It is ten units, as the two sides are of 6 and 8 so you must square them both, add them together (which gives you 100) and then square root that, which gives you 10