I don't have an answer for you, but I do have an important hint ... one that will
stand you in good stead as you go further in your mathematical studies:
The reason there's a drawing right next to this question in the book or on the
homework sheet is that the question can't be answered without the drawing.
Answer:
Explanation:
His warning wasn't strong enough although he understood corruption very well.
What he was basically saying is that if the American Colonies did not rule themselves well and honestly they would go down the drain just as Athens did.
Democracy and Freedom are not words on a piece of paper. They must be lived well and attended to every day by all citizens. It is not disagreement that destroys a democracy. It is not listening carefully when someone with an opposing opinion voices it.
There has not been so much hatred in the United States since the Civil War.
Answer:
But what impact is all of this social networking having on young minds?” Teens' developing brains are extremely vulnerable to so much time online, and because they often have difficulty self-regulating their screen time, risks increase which means they are more susceptible to peer pressure and cyberbullying.
Explanation:
Differences between the Troposphere and the Stratosphere:
The troposphere is the lowest level of the atmosphere, so it is in contact with the Earth’s surface. In contrast, the stratosphere is located above the troposphere, so it is not in contact with the Earth’s surface. Humans live in the troposphere, not the stratosphere. People only spend time in the stratosphere is when they are traveling through it on an airplane, or flying through it while riding in a rocket. The air density and air pressure are much lower in the stratosphere. In fact, stratospheric air is too thin for people to be able to survive without pressurized air to breathe.
Answer:
B and C
Explanation:
B. In a given rock sample, the amount of Silicon-32 isotopes gets divided in half about every 170yrs.
This is the concept of half-life. Half life is the time take for half of a radioactive isotope to disintegrate. The shorter the half life the faster the isotope disintegrates.
From the question, we were told that it would take 170yrs for half of the isotope of Silicon to disintegrate to Phosphorus. This is the half life.
C. The half life can be used to determine the amount of Si-32 that has decayed from the time closure temperature was reached.
The closure temperature is very important in radioactivity. It is the temperature at which a system has cooled and there is no resulting disintegration of parent and daughter isotopes.
From first order kinetics, we know that the rate at which radioactive elements decay at any time is directly proportional to the number of radioactive atoms present. A knowledge of the half life helps to figure out the number of atoms that has decayed in time.
