H-Cl pair of atoms has the most polar bond.
Answer:

Explanation:
Hello there!
In this case, according to the given information, it turns out firstly necessary for us to set the equation for the calculation of density and mass divided by volume:

Thus, we can find the mass of the unknown by subtracting the total mass of the liquid to the mass of the flask and the liquid:

So that we are now able to calculate the density in g/mL first:

Now, we proceed to the conversion to lb/in³ by using the following setup:

Regards!
Hello there! With the values of density and volume, you would be able to find the object's mass.
Density is found by dividing the mass by the volume, so you could place in the values of the density and the volume to get the mass.
For example:
500 = mass/10
The 500 being density and 100 being volume. You would use simple math rules and multiply 10 by 500, and you'd get 5000, therefore using the density and volume values and giving you the mass.
I hope I could help you and have a great day!
Answer : The retention time is, 20 min
Explanation :
Retention time : It is defined as the amount of time a compound spends on the column after it has been injected.
Formula of retention time is:

Given:
Distance from injection point to center of peaks = 10 cm
Chart recorded speed = 0.5 cm/min
Now put all the given values in the above formula, we get:

Retention time = 20 min
Thus, the retention time is, 20 min