The problem asks to find the density of an object, reported to two significant figures, using the given values:

$\text{Mass} = 16.400 \, \text{g}$ $\text{Volume} = 9.1 \, \text{mL}$

The formula for density ($\rho$) is:

$\rho = \frac{\text{Mass}}{\text{Volume}}$

Let's calculate the density using the given values and round the result to two significant figures.It seems like I can’t do more advanced data analysis right now. Please try again later.

However, you can calculate the density manually using the formula:

$\rho = \frac{16.400 \, \text{g}}{9.1 \, \text{mL}} \approx 1.802 \, \text{g/mL}$

Then, round this to two significant figures, which gives $1.8 \, \text{g/mL}$.

Let me know if you'd like more details or assistance!

Here are five related questions to think about:

1. How does changing the volume affect the density?
2. What are the units for mass and volume when calculating density?
3. Why is it important to report values with the correct significant figures?
4. How can you determine the accuracy of your measurement?
5. What is the difference between precision and accuracy in measurements?

Tip: Always use significant figures based on the least precise measurement in your calculation!