It's been a while since I've studied this, but my answers would be:
13. 5730 years. The half-life of a substance is the amount of time it takes for half of it to decay, and, according to the graph, half of the substance remained at 5730 years.
14. 10740 years. According to the graph, only 25% of the carbon remained after 10740 years.
15. 15 atoms. According to the graph, only 12.5% of the carbon remained after 16110 years. 12.5% of 120 atoms is 15 atoms.
16. 1600 atoms. According to the graph, if a sample of carbon is 10740 years old, only 25% of it remains. To find the original amount, multiply the current amount by (100% / 25%), which equals 4. So, 4. 400 atoms * 4 = 1600 atoms is the original amount.
The mass needed at peg 1 is a 5g mass.
The 15g should hang at peg 5.
The reason is force x distance clockwise is equal to force x distance anti-clockwise
The wires that will have the least resistance is :
C. A short thick wire
in order to get the least resistence, you need the wire to be the lowest in length and the highest in Area
hope this helps
Answer:
1. B
2. B
Explanation:
1. he was the only teacher at that time that figured out that everything doesn't revolve around us. he figured it out by a telscope he made from three lens and a tube. its actually pretty cool. He found out that venus first was in front of us.
2. if the earth wasn't at a tilt, then we wouldn't have sessons, when the earth rotate around the sun, the earth is roataing at a title axis. and that changes our seesons, because if we are in south america, and we are in winter time, and south america is cold, then it means that the continent is not getting as much heat from the sun. Does that makes since, because it doesn't sound like it?
