Question

which information can be obtained by using only relative dating methods?
determining the geological period in which an unconformity occurred
determining the type of rock found in the rock layer
determining the true age of rock layers
determining the order of rock layers

Explanation:

Relative dating methods are used to determine the order of rock layers (stratigraphy). They do not give the true age (absolute dating is for that), nor the type of rock (mineralogical analysis needed), and determining the geological period of an unconformity often requires more than just relative dating (absolute dating might be involved too).

Answer:

determining the order of rock layers