Answer:
A sample of 5.2 mg decays to .65 mg or to 1/8 of its original amount.
1/8 = 1/2 * 1/2 * 1/2 or 3 half-lives.
3 * 30.07 = 90 yrs for 5.2 mg to decay to .65 mg
You can get these other numbers similarly:
5.2 / .0102 = 510 requires about 9 half-lives which is 30 * 9 = 270 yrs
Answer:

Explanation:
The rotated angle is given by:

Since this is a quadratic equation it can be solved using:

Rewriting our equation:


Since
we discard the negative solution.

Answer:
See below.
Explanation:
Cubit is a unit of length based on the length of the forearm from the elbow to the tip of the middle finger and usually equal to about 18 inches (46 centimeters).
It is an ancient unit of length used in ancient Egypt and is also known as "ancient Egyptian royal cubit."
Other similar units of measurements are displayed in the image below. Thanks!
A. krypton (atomic mass 83.8 amu)
B. argon (atomic mass 39.95 amu)
C. xenon (atomic mass 131.3 amu)
D. radon (atomic mass 222 amu)
hope this helps!
The thermal energy was produced is 116J
<h3>What is the thermal energy produced?</h3>
Now we know that the frictional force produces the energy that is lost as heat as the body slides down the incline. The magnitude of the frictional force is obtained from;
Ff= μmgcosθ
Ff = 0.65 * 5.0 kg * 9.8 m/s^2 * cos 25
Ff = 29 N
Hence, the thermal energy is;
29 N * 4.0 m = 116J
Learn more about frictional force:brainly.com/question/1714663
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