Answer:
The first source of energy in a food chain is producer.
Explanation: In the food chain, the producer will be a plant that a primary consumer, a herbivore eats. The herbivore gets eaten by a secondary consumer, carnivorous. When the carnivore dies, it becomes energy for a decomposer.
Mass - Yes - Yes
Drop height - Yes - Yes
Initial velocity - No - No
Acceleration due to gravity - Yes - Yes
Object size - No - No
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