Answer:
C. Slope and 
Step-by-step explanation:
We're missing the graph itself, but I can make an educated guess:
- Assuming x = volume and y = mass:

density = mass/volume
x = volume = run
y = mass = rise
mass/volume = rise/run = slope
The slope of the line (assuming the graph is purely linear) represents mass/volume, which is the formula for density.
I had to Google the density of silver itself. Do the math from the graph for a more appropriate answer, as the graph may be less scientifically precise.
Answer:
4 2/4
Step-by-step explanation:
3/4 + 3/4 + 3/4 + 3/4 + 3/4 + 3/4
640 is your answer. 5 1-gallon jugs=640 fluid ounces.
6 cups.
2/5 of the mixture would be lemon juice, and 2/5ths of 15 is 6