Explanation:
Using stratified random sampling, researchers must identify characteristics, divide the population into strata, and proportionally choose individuals for the representative sample. ... For example, individuals who are too busy to participate will be under-represented in the representative sample.
Answer:
Would it be<em><u> 7.69 seconds</u></em>?
Explanation:
Answer:
Landslides, Volcanoes, Earthquakes, and Floods. A opening in the Earth's surface through which melted rock, gases, and ash escape. Events in which molten rock spews out from the mantle to the surface of Earth as ash, lava, and gases
Explanation:
<h3>
Answer:</h3>
8 alpha particles
4 beta particles
<h3>
Explanation:</h3>
<u>We are given;</u>
- Neptunium-237
- Thallium-205
- Neptunium-237 undergoes beta and alpha decay to form Thallium-205.
We are required to determine the number of beta and alpha particles produced to complete the decay series.
- We need to know that when a radioisotope emits an alpha particle the mass number reduces by 4 while the atomic number decreases by 2.
- When a beta particle is emitted the mass number of the radioisotope increases by 1 while the atomic number remains the same.
In this case;
Neptunium-237 has an atomic number 93, while,
Thallium-205 has an atomic number 81.
Therefore;
²³⁷₉₃Np → x⁴₂He + y⁰₋₁e + ²⁰⁵₈₁Ti
We can get x and y
237 = 4x + y(0) + 205
237-205 = 4x
4x = 32
x = 8
On the other hand;
93 = 2x + (-y) + 81
but x = 8
93 = 16 -y + 81
y = 4
Therefore, the complete decay equation is;
²³⁷₉₃Np → 8⁴₂He + 4⁰₋₁e + ²⁰⁵₈₁Ti
Thus, Neptunium-237 emits 8 alpha particles and 4 beta particles to become Thallium-205.
Answer:
My role models are my parents. They are my pillars of strength. They are my guide and give me the courage to battle obstacles in life.
My mother, being a working professional, manages all her work perfectly and with efficiency.
My father goes to office, but still does not forget to help me with my studies. They always encourage me in every aspect and motivate me even when I do not succeed.
My mother always smiles, no matter what the circumstances are and that gives me the strength and inspiration to face all problems.
My parents have made me understand what life is about and how to find that little ray of happiness in difficult situations.
What I am today and what I will become in future involves the support and affection of my parents. They have made me disciplined, dedicated and sincere.
A role model does not have to be a famous personality. It can be anyone who makes us believe in ourselves.
My parents fill sweetness in my life. From childhood I have learnt everything from my parents.
Not just parents, I also consider my teachers as role models. Even they guide me and show the path of success.
They have turned me into a fighter in the war of life
