Answer: To know if a document is a primary source, check to see when the document is published, if it is an autobiography of a person, a diary, a letter, or the documents happen at the time of the event.
The competition between two organisms can be seen if there is only 1 source of food or habitat space and they're competing against each other for the food or habitat.
There is cooperation between two organisms if they are helping each other with resources or alarming each other if there is danger.
Predation between two organisms happen when one organism hunts the other organism for food.
Some other secondary consumers are carnivores and others are omnivores because they also eat both plants and meat. For example Human, human are secondary consumers, and human eat both plants and meat. There are also other animals that are considered as omnivores.
Answer:
The force of friction is reduced between the blocks by adding the dishwashing liquid because the liquid is slippery and this makes it difficult for the two surfaces to contact each other directly. Therefore the blocks slip past each other rather than grinding against each other, producing less friction.
Explanation:
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