The man has donated 500ml of Blood1.The human body can produce 2.5 million blood cells per second. If a person donates 500 mL of blood, how long will it take to replace the red blood cells if a litre of blood contains 5 × 10^12 red blood cells?
so he has donated
Which he needs to recover at the rate of 2.5 x 10^6 blood cells per second
Hence lets say it takes n seconds to do so
Hence n = 10^6 second = 10,00,000 second
2.The Sun is approximately 1.5 × 10^8 km from Earth and a comet is approximately
3 × 10^6 km from Earth. How many times further from Earth than the comet is the Sun?
Distance of sun from comet = 1.5 \times 10^8
Distance of sun from earth = 3 \times 10^6
Your question asks the ratio of these distances
it will be given by
Thus it is 50 times the distance of sun and earth