The total distance covered by the person is 12 times the height of each stair:
The work done by the person to climb the stairs is equal to the increase in his gravitational potential energy:
And therefore, the power generated by the person in 12 s is the work done divided by the time taken:
So, the correct answer is B.
Refractor, It's a refractor-esque telescope
Atomic mass (z) - atomic number / # of protons (n) = # of neutrons:
151-54=97
You can easily tell what element X is. With an atomic number of 54, the element is the noble gas Xenon (Xe).
Simple.
1 mile = 1.6 km
So simply, 20,000 miles = 20,000 × 1.6
which is equal to 32,000km
Hope it helps dear friend ☺️
200 meters per minutes
500 meters -300 meters= 200 meters
300 meters -100 meters =200 meters