The answer is A : 302 I really hope this helps!
Answer:
42.11 years old
Explanation:
Given that:
In 2000, a 20-year-old astronaut left Earth to explore the galaxy; her spaceship travels at 2.5 x 10^8 m/s. She returns in 2040
To find her age we use:
Δtm is time interval for the observer stationary relative to the sequence of
events = 2040 - 2000 = 40 years
Δts is is the time interval for an observer moving with a speed v relative to the sequence of event
v = velocity = 2.5 x 10^8 m/s
c = speed of light = 3 x 10^8 m/s
Here age in 2000 is 20 year, therefore when she appear she would be 20 year + 22.11 year = 42.11 years old
To Find :
Which element accumulates in the environment due to the use of fertilizers.
Solution :
Most of the fertilizers used in daily practice are nitrogen fertilizers .
When soil became waterlogged, soil organisms take the oxygen they need from nitrates, leaving the nitrogen in a gaseous form which escapes into the air.
Also, nitrogen is very stable and did not participate in most of the reactions.
So, nitrogen is accumulates in the environment .
Therefore, option C. is correct.
There is synthesis
decomposition
double displacement
single displacement
combustion
metathesis
so i guess you could say 6