How much work would an 80 kg person have to do in order to lift his/her own body weight up the entire flight of stairs of the Empire State building (FYI: 1576 stairs!), which is 320
meters high?

Ithink it’s 98 because jajajjajansmsmjs

The fertilized egg  begins to develop into a hollow ball of cells called the blastocyst. 

Iwould think it would be efficiency.

Distance covered = speed x timethe distance traveled going against the stream = distance traveled with the stream.therefore it is the speed and the time that are the variables.as he travels the same distance both ways, speed x time is the same for each way.going upstream his speed is 4 kph; going downstream his speed is 6 kph.therefore we have two simultaneous equations: time upstream x 4 = time downstream x 6time upstream + time downstream = 60 minutestherefore we have the equation: time upstream = 6/10 hour, time downstream therefore = 4/10 hour.distance traveled at 4km/hr in 6/10 hour = 24/10 = 2.4km.check: distance traveled at 6km/hr in 4/10 hour = 24/10 = 2.4km.