#Given
AB=2*10**5 #m
CN=100 #km
C=3.0*10**8
#Calculation
Tg=AB/C
Q=(math.sqrt(CN**2+CN**2))+(math.sqrt(CN**2+CN**2))
Ts=Q*10**3/C
W=(Ts-Tg)
#Result
print"The time delay is",round(W*10**4,2),"*10**-4 s"
#Given
H=80 #m
R=6.4*10**6
W=800 #km**-2
#Calculation
import math
D=math.sqrt(2*H*R)
A=math.pi*D**2
S=A*W
#Result
print"(a) The radius of the circle is",D*10**-4,"10**4 m"
print"(b) The population covered by the transmission is",round(S*10**-12,3),"*10**6"