Answer: 8.1e+2 or 8.1E+2 (in the scientific notation mode), based on that the number given is 8.1 × 10².
Explanation
Scientific calculators use the letter e or E to show the numbers in scientific notation mode.
These are some examples of numbers that require scientific notation and how they are shown.
Number Scientific calculator display
6.022 × 10²³ 6.022 e+23
5 × 10 -12 5 E -12
So, understanding that your question is about number 8.1 × 10², the scientific calculator could show 8e+2.
Nevertheless, since 8 .1 × 10² is 810, not a long number, if the display is not in scientific notation mode, it could just display just 810,
Answer:
1 g
Explanation:
The half-life of Am-242 (16 h) is the time it takes for half of it to disappear.
We can make a table of the mass left after each half-life.

The mass remaining after 48 h is 1 g.
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