Answer:
A = 349 g.
Explanation:
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In this case, since the radioactive decay kinetic model is based on the first-order kinetics whose integrated rate law is:

We can firstly calculate the rate constant given the half-life as shown below:

Therefore, we can next plug in the rate constant, elapsed time and initial mass of the radioactive to obtain:

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<em>Same group element have same</em><em><u> Valence electron</u></em><em> and behave similarly in </em><em><u>Chemistry.</u></em>
<u>Explanation:</u>
For example. First group elements Alkali metals:- H, Li, K, Rb, Cs, Fr
Valance electron will take part in forming a bond with other elements and compound will form. All the above-given elements (H-Fr) have valence electron 1 in outer most 'S' shell. All have electronic configuration S1
Behavior: Since valence electrons are the same so the behavior of all the elements in this group is the same. All are metal (from Li-Fr, except Hydrogen), all are very reactive, does not found in native state in the environment, and all react with water.
Answer:
The clouds that carry the dust can be huge, and miles long. They can rise to be over 305m. They also have wind speeds of at least 40 kilometers.Sandstorms can happen really quickly.
Explanation:
Sandstorms carry with them large volumes of sand and dust. But more than sand, they also carry with them virus spores that interact with the atmosphere. Because of this, I can contact any disease from it.
Other immediate effects of sandstorms to me include the worsening of lung functions if I have asthma. Due to inhalation of large amounts of dust, dust pneumonia could be developed. Diseases such as silicosis could also develop from prolonged exposure to sand. If left untreated, it will eventually lead to asphyxiation and lung cancer. The eyes could also be affected by the particles. Keratoconjunctivitis sicca, or dry eyes, could develop which could lead to blindness. My exposure to sandstorms could have adverse effects on my circulatory system. So I could either die immediately or fall terrible sick it depend on my health issue.
Stars born larger than 8 solar masses usually retain enough mass to undergo core collapse, with the resulting shock wave producing a Type Ib supernova (spectra without Hydrogen or Silicon lines, with Helium lines), a Type Ic supernova (without Hydrogen or Helium or Silicon lines) or a Type II supernova
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