Final answer:
The local standard time in Chicago (90W) when a satellite image of the United States was taken at 0900Z would be 3 am.
Step-by-step explanation:
In the United States, the time zones are usually expressed in relation to Coordinated Universal Time (UTC). Chicago is located at 90W longitude, which is in the Central Standard Time (CST) zone.
The standard time in CST is 6 hours behind UTC. Therefore, if a satellite image of the United States was taken at 0900Z (9:00 a.m. UTC), the local standard time in Chicago would be 3 am.