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Updated on: 03 Jul 2025, 10:28 
Dropdown 1: 19.5
Dropdown 2: 1.8
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
95%
(hard)
Question Stats:
30% (03:05) correct
70%
(02:46)
wrong
based on 230
sessions
History
Date
Time
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Not Attempted Yet
A Mars rover is analyzing samples from different soil layers to determine how the presence of a radioactive isotope has changed over time. The decay of the isotope follows a predictable pattern, and the data below was recorded at various time intervals after initial measurement. The half-life of the isotope is estimated to be between 15 and 25 hours.
Based on this data, answer the following questions:
After approximately every hours, the concentration appears to halve itself.
From hour 10 to hour 30, the average rate of decay in mg/g per hour is approximately .
chart (8).png [ 19.25 KiB | Viewed 376 times ]
Based on this data, answer the following questions:
After approximately every hours, the concentration appears to halve itself.
From hour 10 to hour 30, the average rate of decay in mg/g per hour is approximately .
Attachment:
chart (8).png [ 19.25 KiB | Viewed 376 times ]
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Official Answer
Dropdown 1: 19.5
Dropdown 2: 1.8
