It's been a while since I've studied this, but my answers would be:
13. 5730 years. The half-life of a substance is the amount of time it takes for half of it to decay, and, according to the graph, half of the substance remained at 5730 years.
14. 10740 years. According to the graph, only 25% of the carbon remained after 10740 years.
15. 15 atoms. According to the graph, only 12.5% of the carbon remained after 16110 years. 12.5% of 120 atoms is 15 atoms.
16. 1600 atoms. According to the graph, if a sample of carbon is 10740 years old, only 25% of it remains. To find the original amount, multiply the current amount by (100% / 25%), which equals 4. So, 4. 400 atoms * 4 = 1600 atoms is the original amount.
............................................................................... Hello wonderful person <3
The time taken for the first p-wave to reach the same seismic station is approximately 13 minutes.
<h3>Time of travel of the P-wave</h3>
In rock, S waves generally travel about 60% the speed of P waves, and the S wave always arrives after the P wave.
<h3>Relationship between speed and time</h3>
v ∝ 1/t
v₁t₁ = v₂t₂
t₁/t₂ = v₂/v₁
t₁/t₂ = 0.6v₁/v₁
t₁/t₂ = 0.6
t₁ = 0.6t₂
t₁ = 0.6 x 22 mins
t₁ = 13.2 mins
Thus, the time taken for the first p-wave to reach the same seismic station is approximately 13 minutes.
Learn more about P-waves here: brainly.com/question/2552909
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