In the given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, what will be the energy available at the producer level?
Grass `to`
Grasshopper`to`
Frog `to` Snake `to`
Hawk

Options

A. 5 kJ
B. 50 kJ
C. 500 kJ
D. 5000 kJ

Explanation

To solve the problem, we need to understand the concept of energy transfer in a food chain, specifically the 10% rule of energy transfer between trophic levels. Here’s how we can calculate the energy available at the producer level step by step:

### Step-by-Step Solution:

1. **Identify the Trophic Levels**:
- In the given food chain, we have:
- Trophic Level 1: Grass (Producers)
- Trophic Level 2: Grasshopper (Primary Consumers)
- Trophic Level 3: Frog (Secondary Consumers)
- Trophic Level 4: Snake (Tertiary Consumers)
- Trophic Level 5: Hawk (Quaternary Consumers)

2. **Energy at the Fourth Trophic Level**:
- We are given that the energy at the fourth trophic level (Snake) is 5 kJ.

3. **Apply the 10% Energy Transfer Rule**:
- According to the 10% rule, only 10% of the energy from one trophic level is transferred to the next.
- Therefore, if the energy at the fourth trophic level (Snake) is 5 kJ, we can find the energy at the third trophic level (Frog) using the formula:
\[ \text{Energy at Frog} = \frac{\text{Energy at Snake}}{0.1} = \frac{5 \text{ kJ}}{0.1} = 50 \text{ kJ} \]

4. **Calculate Energy at the Second Trophic Level**:
- Now, we calculate the energy at the second trophic level (Grasshopper):
\[ \text{Energy at Grasshopper} = \frac{\text{Energy at Frog}}{0.1} = \frac{50 \text{ kJ}}{0.1} = 500 \text{ kJ} \]

5. **Calculate Energy at the Producer Level**:
- Finally, we calculate the energy at the first trophic level (Grass):
\[ \text{Energy at Grass} = \frac{\text{Energy at Grasshopper}}{0.1} = \frac{500 \text{ kJ}}{0.1} = 5000 \text{ kJ} \]

### Final Answer:
The energy available at the producer level (Grass) is **5000 kJ**.

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