As the density of the unknown substance is 0.68g/0.8ml = 0.85g/ml, it is less dense than the maple syrup at 1.33g/ml and will float.
Given:
Work done, W = 5 J
Initial energy = 8J
Final energy = 30J
Let's determine if the work done have a positive or nrgative value.
Appy the equation for the first lae of thermodynamics:

Where:
U is the change in internal energy
Q is the added heat
W is the work done
To find the work done here, we have:
Rewrite the formula for W

Where:
ΔU = 30J - 8J = 22J
Q = 5J
Thus, we have:

Therefore, the work done here is -17J.
This means the work done in this scenario has a negative value.
ANSWER:
The work done in this scenario has a negative value
Answer:
Scientists have determined that humans are disrupting the nitrogen cycle by altering the amount of nitrogen that is stored in the biosphere. The chief culprit is fossil fuel combustion, which releases nitric oxides into the air that combine with other elements to form smog and acid rain.