- If something can be used to determine a property of something else then that something can likely be used to determine that property of a part of that something else
- Age is a property of rocks
- So, if something can be used to determine the age of a rock then that something can likely be used to determine the age of a part of a rock

- If something can be used to determine the age of a rock then that something can likely be used to determine the age of a part of a rock
- The law of superposition can be used to determine the relative age of the rock
- So, the law of superposition can be used to determine the relative age of part of a rock

- The law of superposition can be used to determine the relative age of part of a rock
- Sedimentary rock is a kind of rock
- Hence, the law of superposition can be used to determine the relative age of a part of sedimentary rock

- The law of superposition can be used to determine the relative age of a part of sedimentary rock
- Layers are a part of sedimentary rock
- So, the law of superposition can be used to determine the age of sedimentary rock layers

So, the law of superposition can be used to determine the age of sedimentary rock layers
Question
A hillside along a highway has exposed layers of undisturbed sedimentary rock. Which method would be best for scientists to use to determine the relative age of these sedimentary rock layers?

Context
- Sedimentary rock is a kind of rock 
- Layers are a part of sedimentary rock 
- If something can be used to determine a property of something else then that something can likely be used to determine that property of a part of that something else 
- The law of superposition can be used to determine the relative age of the rock 
- Age is a property of rocks