Before the development of isotopic dating methods, scientists estimated the age of the Earth by: ___________
a. estimating eruption rates of volcanoes.
b. comparing rates of change on the Earth's surface today with the geologic record.
c. counting tree rings.
d. determining the time it takes to create fossils like shark teeth.
B. comparing rates of change on the Earth's surface today with the geologic record.
Here's some other possible answers:
Counting generations in the bible, comparing rates of change on Earth's surface today with the geologic record, calculating the cooling history of the Earth, estimating evolution rates from the fossil record