Question

which is not one of the three methods used to estimate the age of the earth?
the rate of sedimentation
measurements of the rate of decay in radioactive materials
measurements of the number of rings in tree trunks
measurements of the saltiness of the ocean

Explanation:

To determine which is not a method to estimate Earth's age, we analyze each option:

• Sedimentation rate (used to estimate Earth's age by analyzing sediment layers).
• Radioactive decay (a key method, like radiometric dating, to estimate Earth's age).
• Tree rings (dendrochronology) are used to date events in relatively recent history (hundreds to thousands of years), not to estimate the Earth's age (billions of years).
• Ocean saltiness (by calculating how long it would take for oceans to reach current salinity from a freshwater start, used to estimate Earth's age).

So measuring tree rings is not a method for Earth's age estimation.

Answer:

C. measurements of the number of rings in tree trunks