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Eva8 [605]
2 years ago
13

Also need help with 20 & 21 please

Physics
2 answers:
SSSSS [86.1K]2 years ago
5 0
Number 20 is B and 21 is C
Hoochie [10]2 years ago
5 0
A density is a physical change
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a sample contains 100 g of radioactive isotope. How much radioactive isotope will remain in the sample after 1 half-life?
kap26 [50]

Answer:

\huge\boxed{50g}

Definition:

Half-life- The time taken for half of the radioactive isotopes to decay.

Explanation:

How does radioactive decay work? Radioactive decay is a process by which unstable nuclei become more stable through the emission of alpha or beta particles or gamma rays.

Since a half-life is the time taken for half of the isotopes to decay, we can simply divide the initial mass of 100 grams by 2; this gives us 50 grams.

1) Divide 100g by 2.

\frac{100g}{2}=50g

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1 year ago
Why are circuit breakers and fuses important?
Lesechka [4]

Answer:

A fuse and circuit breaker both serve to protect an overloaded electrical circuit by interrupting the continuity, or the flow of electricity. ... Fuses tend to be quicker to interrupt the flow of power, but must be replaced after they melt, while circuit breakers can usually simply be reset.

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creativ13 [48]

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Explanation:

Deer = primary consumer

Green plants = producer

Fungi = decomposers

3 0
2 years ago
Melting, freezing, and boiling are______ changes
avanturin [10]
Melting, boiling, and freezing are state changes!
Hope this helps! Any questions please just ask! Thank you so much!
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