Answer:
<h2>mass = 29.25 g</h2>
Explanation:
The denisty of a substance can be found by using the formula

Making mass the subject we have
<h3>mass = Density × volume</h3>
From the question
Density = 2.34 g/mL
volume = 12.50 mL
Substitute the values into the above formula and solve for the mass
That's
mass = 2.34 × 12.50
We have the final answer as
<h3>mass = 29.25 g</h3>
Hope this helps you
Answer : At constant pressure work is done by the system on the surroundings.
Explanation :
Work done : Any quantity that flows across the boundary of a system during a change in its state and it completely convertible into the lifting of a weight in the surroundings.
Formula for work done is:

Sign convention :
- When volume expand then system work that means work done by the system.
w = (-ve)
- When volume compress then surrounding work that means work done on the system.
w = (+ve)
The given reaction is:

This is a evaporation process in which phase changes from liquid state to gaseous state at constant temperature.
At constant pressure, work depends only on volume.
In evaporation process, the volume expand that means work is done by the system on the surroundings.
Sign convention is, w = (-ve)
Thus, at constant pressure work is done by the system on the surroundings.
The correct should be A. thousands of galaxies
Answer:
A) increasing tension in the vibrating object.