Table 2. Estimated minimum values for 
.
|
 (hours) |
| 10 |
|
| 15 |
|
| 20 |
|
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.