A virus known to cause a deadly disease, is also a rapid multiplier. It is known that it can double itself every 30 minutes. If a container is completely full of this virus after 50 hours, when was the container half empty?$?

A virus known to cause a deadly disease, is also a rapid multiplier. I

1.	A virus known to cause a deadly disease, is also a rapid multiplier. It is known that it can double itself every 30 minutes. If a container is completely full of this virus after 50 hours, when was the container half empty?$?
A.	35 hours
B.	49.5 hours
C.	46 hours
D.	20 hours
Answer» C. 46 hours