It is C. because the sunlight bounces off the moon causing it to be visible only at night.
Percentage by volume of solution is the percentage volume of solute in total volume of solution.
Volume percentage (v/v%) = volume of solute / total volume of solution x 100%
volume of solute - 16.0 mL
total volume of solution - 155 mL
v/v% = 16.0 / 155 x 100% = 10.32%
this means that in a volume of 100 mL solution, 10.32 mL is acetone.
Answer:
100 J of energy are needed to heat the copper from 20∘C to 80∘C .