Answer:
d
Step-by-step explanation:
The answer is 400 + .04. Or if you want a big answer, then it would be. 400 + 00 + 0 + .0 + .04.
Answer:
t = 1/2 hour
Step-by-step explanation:
20480 = 80
20480 = 80
20480/80 = 
256 = 
x = 4
doubling period
2 = 
t = 1/2 hour