Step 1: Calculate the Present Value of Benefits and Costs for each year.
\[ {PV of Benefits}_t = {Benefits}_t \times {Discount Factor}_t \]
\[ {PV of Costs}_t = {Costs}_t \times {Discount Factor}_t \]
For each year:
- Year 0:
\[ {PV of Costs} = 89 \times 1.00 = 89,000, \quad {PV of Benefits} = 0 \]
- Year 1:
\[ {PV of Benefits} = 25 \times 0.96 = 24,000, \quad {PV of Costs} = 5 \times 0.96 = 4,800 \]
- Year 2:
\[ {PV of Benefits} = 25 \times 0.92 = 23,000, \quad {PV of Costs} = 5 \times 0.92 = 4,600 \]
- Year 3:
\[ {PV of Benefits} = 25 \times 0.89 = 22,250, \quad {PV of Costs} = 5 \times 0.89 = 4,450 \]
- Year 4:
\[ {PV of Benefits} = 25 \times 0.85 = 21,250, \quad {PV of Costs} = 5 \times 0.85 = 4,250 \]
- Year 5:
\[ {PV of Benefits} = 25 \times 0.82 = 20,500, \quad {PV of Costs} = 5 \times 0.82 = 4,100 \]
Step 2: Calculate the Total Present Value of Benefits and Costs.
\[ {Total PV of Benefits} = 0 + 24,000 + 23,000 + 22,250 + 21,250 + 20,500 = 110,000 \]
\[ {Total PV of Costs} = 89,000 + 4,800 + 4,600 + 4,450 + 4,250 + 4,100 = 111,200 \]
Step 3: Calculate the Net Present Value (NPV).
\[ {NPV} = {Total PV of Benefits} - {Total PV of Costs} \]
\[ {NPV} = 110,000 - 111,200 = -1,200 \]
Final Answer: The net present value (NPV) of the plant is \(\boxed{-200}\).