Velocity is distance/time
so 150/7200=.0208km/s
unless you have to convert it to miles or something else. but use the formula!
Well, there would have to major supports on every building that was tall even though we have very strong foundation the foundation doesn't do anything except no give us dirt as a floor.but a really strong structure to use is a triangle formation.
Hope this helped
density = mass/volume = 100kg/10ml = 10kg/ml
voluime = mass/density = 50g/2 g/ml = 25 ml
mass = density x volume = 2x55 = 110 kg
