Hulu
Please see http://www.hulu.com/help/articles/21148167 for Hulu Settings.
Netflix
Watching Netflix uses about 1 GB of data per hour for each stream of standard definition video, and up to 3 GB per hour for each stream of HD video.
Adjust your data usage settings
Adjusting the data usage settings for your account is the easiest way to reduce the amount of bandwidth used while watching Netflix. There are 4 data usage settings to choose from, each estimate below is per stream: