Answer:
The artifact is 11,460 years old.
<u>Explanation</u>:
Given that,
The half life of the carbon-14 is 5730 years and we are left with 255 of the sample of wood from an arti-fact.
So it takes 5730 years for the sample to reduce into half
Initially there will be 100% of the sample so
after first 5730 years, the sample reduces into 50% percent
Now the left 50% sample will take another 5730 years to decay into half of its amount.
after next 5730 years the sample reduces into 25% percent
So totally after 2 half-life the sample reduces into 25%
That is (5730 +5730) years = 11460 years
Answer:
The balloon will continue to expand and eventually burst.
Explanation:
Simply, the reason for this is because the density of the atmosphere decreases gradually as you increase in altitude closer to space. This means that the air on the outside of the balloon can't provide enough pressure over the surface of the balloon in order to counteract the gas on the inside of the balloon from expanding.
1.8 mol of Na. hope this helps
Answer:
(a) 
(b) 
(c) 
Explanation:
(a) According to Newton's second law, the acceleration of a body is directly proportional to the force exerted on it and inversely proportional to it's mass.

(b) According to Newton's third law, the force that the sled exerts on the girl is equal in magnitude but opposite in the direction of the force that the girl exerts on the sled:

(c) Using the kinematics equation:

For the girl, we have
and
. So:

For the sled, we have
. So:

When they meet, the final positions are the same. So, equaling (1) and (2) and solving for t:

Now, we solve (1) for 

252-364 licks
I'm not sure if it's correct or not