Question

question 1
which of the following is a characteristic of all rocks?
they are a collection of minerals or a body of glass
they can be manufactured for commercial use
they have a definite chemical composition
all of the above

Explanation:

• Rocks are naturally - occurring. So, the option "they can be manufactured for commercial use" is incorrect as manufacturing implies a non - natural process.
• Minerals have a definite chemical composition, but rocks (which are made of minerals or glass - like substances) do not have a definite chemical composition. For example, granite is a rock made of quartz, feldspar, and mica, and its exact composition can vary.
• By definition, rocks are a collection of minerals or a body of glass (such as obsidian, which is a volcanic glass and considered a rock).

Answer:

they are a collection of minerals or a body of glass