Spontaneous at low temperatures.
Radiography techs are trained to operate medical equipment that uses X-rays and other types of radiation. Ultrasound techs, referred to professionally as diagnostic medical sonographers, operate equipment that uses high-frequency sound waves to create images.
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<h3><u>Answer;</u></h3>
= 11,460 years
<h3><u>Explanation;</u></h3>
- <em><u>The half life of Carbon-14 is 5,730 years
. Half life is the time taken by a radioactive material to decay by half of its original mass. Therefore, it would take a time of 5730 years for a sample of 100 g of carbon-14 to decay to 50 grams</u></em>
<em>The initial amount of carbon-14 in this case was 1 whole; thus; </em>
<em>1 → 1/2 →1/4</em>
<em>To contain 1/4 of the value, 2 half-lives have passed.
</em>
<em>But, 1 half life = 5,730 years</em>
<em>Therefore; The artifact is is therefore: 2 x 5,730
</em>
<em> = 11,460 years </em>
<u>Answer:</u>
<em>Atomic number 75 is dedicated to an element named rhenium and has been given Re as its chemical name.</em>
<u>Explanation:</u>
With a really low concentration it is one of the rarest metals that is found in Earth's crust.
Like all other elements rhenium also has certain isotopes among with 185 and 187 are the most stable ones. Hence these two are the ones that are naturally available abundance is 34% and 63% respectively.