Suppose you want to perform a scientific investigation to find out how high a ball bounces on diferent kinds of surfaces. What are appropriate materials to reference before beginning your investigation? What are examples of
appropriate reference materiais?

you didn't give any options but heres what i can tell you: an inference is likely to change based on additional observations. the latter is something that you have seen or sensed using your sensory organs while the former is like a conclusion out from what you have observed.

sodium i think the chemical element of atomic number 11, a soft silver-white reactive metal of the alkali metal group.