Calculator 

surface area of sphere = 4πr2     [* π 2][exponents]
Earth radius is 3958.8 mi
surface area of Earth = ___________

volume of sphere = 4/3 πr3       [fractions]   [r=1,2,4 V=]
volume of Earth = ___________ 

Visualize area → square       [sqrt √, simplify] [cube root...]
Earth area as a square. side = ___________ 

Earth is 29% land, 71% ocean.      [p% of x = p/100 * x]
Land on Earth =  ___________

CONUS is 2,959,064.44 square miles of land.
percent of world's land that is CONUS =  ___________              [1/x]

Earth's orbit around sun is basically circular. C = 2πr = dπ
Earth distance from sun is 93M mi
distance Earth travels in one year (one revolution around sun) = 
speed in miles per hour =  ___________

Gallon of water weighs 3778 g.     1kg = 2.2046 lbs
weight in pounds =  ___________           


Distance in km to thing at height h2 above sea level 
 given one's height h1 above sea level in meters = 3.57(√h1 + √h2)
You at 100m, distant thing 300m, what's the farthest apart they can be to be seen?
Empire State Bldg's 102nd floor observatory is 373m above street (+~50' above sea level)
   how far is the horizon?

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kilogram of water: volume is 1 liter.
Human body is 2/3 water and almost same density as water.
Your weight in kg  → your volume in liters = ___________
  Gallon=3.785 L   → your volume in gallons = ___________  

BSA m2  = √1.15wh / 60    lbs ins       [1m2=10.764ft2]
 ___________

BMI = 703 w/ h2     lbs ins
body mass index
 ___________

BRI = 364.2 - 365.5*√(1-(waist/(pi*height))2)
body roundness index  3-6 is good
 ___________

BMR = 10*kg +6.25*cm - 5*age + (M:5, F:-161)
day
 ___________