"""
Ex. 1.12 from "A primer on..."
"""

from numpy import pi, log

M = 47      #mass for a small egg
rho = 1.03
c = 3.7
K = 5.4e-3

To = 4     #initial temperature (fridge)
Tw = 100   #water temperature
Ty = 70    #target temperature for the yolk

t = (M**(2/3) * c * rho**(1/3)) / (K * pi**2 * (4 * pi/3)**(2/3)) \
    * log(0.76 * (To - Tw)/(Ty - Tw))

print(t)

#or, for slightly more sophisticated output:
minutes = int(t/60)
seconds = int(t%60) #% is the modulo ("rest") operator
print(f"The egg is ready after {minutes} minutes and {seconds} seconds")