Question

what can be concluded about the age of the rock sample?
sample number | physical characteristics | radiometric age (millions of years)
1 | dark gray; fine grain | 50
2 | medium gray; fine grain | 120
3 | light gray; medium grain | 210
4 | medium gray; medium grain | 300
a the rock is approximately 50 million years old because it shares characteristics with sample 1
b the rock is approximately 120 million years old because it shares characteristics with sample 2
c the rock is approximately 210 million years old because it shares char
save/exit

Explanation:

To determine the rock's age, we analyze physical characteristics and radiometric ages of samples. Sample 2 has "medium gray, fine grain" and age 120 million years. If the rock shares these characteristics, its age should match Sample 2's (120 million years), so option B is correct.

Answer:

B. The rock is approximately 120 million years old because it shares characteristics with Sample 2