The original sample will be around after 3.5 seconds | Quick Homework Help

1. 2b. Assume you have a sample of atoms with a half-life of 0.5 second. Approximately how much (in %) of the original sample will be around after 3.5 seconds? * Choose the answer closest to the exact value.

• 0.1%
• 0.3%
• 1%
• 3%
• 10%
• 30%
• 100%

2c. Potassium-40 decays to Argon-40 with a half-life of 1.25 billion years old. If at the formation of the Earth we had 100% Potassium-40 and 0% Argon-40, what should be ratio of Potassium-40 / Argon-40 on the Earth today? * choose closest answer

• 0.05
• 0.09
• .40
• 0.91
• 1.1
• 2.5
• 3.6
• 11.5
• 20
• 100