Answer: 127.5ml
Explanation:
To calculate the volume of acid, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is KOH.
We are given:

Putting values in above equation, we get:

Thus 127.5 ml of 0.5M of HNO3 would be needed to react with 85ml of 0.75M of KOH
The best answer for this question would be B
C is the answer because he wants to know if less force is needed to pull on a slippery surface which reduces friction
Answer:
The correct answer is - the number of days the rainwater stands in the jars.
Explanation:
The independent variable or the manipulating variable is a variable in a research or study is the variable which affects the dependent variable or the variable that is going to measure in the study.
In the study, variables that recieves the treatment and changed in every subject are independent variables and in this study number of days the rainwater standing in various jars that might affect the growth of the bacteria in rainwater.
<span>Identical particles were produced no matter which metal he used.</span>