For the first one the answer is B. and the second one is D.
The symbol %v/v means percent by volume. Assuming there is no volume effects when these substances are mixed, we calculate as follows:
% v/v = (25 mL ethanol / 25 mL + 150 mL ) x 100
%v/v = 14.29 mL ethanol / mL solution
Hope this answers the question.
They are pretty much the cause and effect. The independent variable that is being changed in the experiment, so it is the cause. The dependant variable is the result of change the independant variable, so the effect.
It is <span>a substance produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction.
So I think C matches the discription </span>
<u>Answer:</u> The correct answer is 
<u>Explanation:</u>
We are given:

The substance having highest positive
potential will always get reduced and will undergo reduction reaction. Here, silver will always undergo reduction reaction will get reduced.
Chromium will undergo oxidation reaction and will get oxidized.
The half reactions for the above cell is:
Oxidation half reaction: 
Reduction half reaction:
( × 3)
Net equation: 
Oxidation reaction occurs at anode and reduction reaction occurs at cathode.
To calculate the
of the reaction, we use the equation:

Putting values in above equation, we get:

Hence, the correct answer is 