Question

1. identify the following as an observation or inference: the brain is preserved because it has been placed in a formaldehyde solution scientific method 21. identify the variables in the following problem: s the amount of

Explanation:

For Question 15:

An inference is a conclusion drawn from evidence or reasoning. Here, the statement explains why the brain is preserved (because of formaldehyde), which is a reasoned conclusion about the cause, not a direct observation (which would be noting the brain looks preserved or is in the solution).

Answer:

Inference

For Question 21:

The problem text is incomplete, so we can't identify the variables without the full question (e.g., the full scenario about "the amount of..." and what it affects). Please provide the complete text of Question 21 to analyze the independent and dependent variables.