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