Question

the organisms in a food chain are listed in order of trophic level from left to right.
plant grasshopper mouse snake hawk
based on the food chain, if a hawk acquires 50 calories of energy, how much energy did the grasshopper get from the plant?
500 calories
5,000 calories
50,000 calories
500,000 calories

Explanation:

Step1: Recall 10% energy transfer rule

Only ~10% of energy moves to the next trophic level, so to reverse, divide by 0.1 (multiply by 10) for each level up.

Step2: Count trophic levels between hawk and grasshopper

Hawk (level 5) → Snake (4) → Mouse (3) → Grasshopper (2): 3 levels up from hawk to grasshopper.

Step3: Calculate grasshopper's energy

Start with hawk's 50 calories, multiply by 10 three times:
$50 \times 10 = 500$ (energy at snake level)
$500 \times 10 = 5,000$ (energy at mouse level)
$5,000 \times 10 = 50,000$ (energy at grasshopper level)

Answer:

50,000 calories