Whining noise

2006 Chevy Trailblazer. I recently noticed a steady shine from the engine that increases in volume as I accelerate. I can hear it while driving in the city but not as much on the highway. Turning the wheel has no effect on the sound. Any thoughts?

At idle as well as acceleration my car makes a terrible whirr/whine, hard to describe. The only thing I do in the vehicle that affects the noise in acceleration however when I am on the freeway at 65 mph cruising or coasting then I can no longer hear the noise. I am not sure when it started but now it is so loud when I start the car or go through a drive through and sit there idling it is down right embarrasing and probably at a decible level that would damage the ears if listened to all day.

After my car has been ilde for awhile, for at least four hours or more, when I go to start It, It will make a very high pitch whinning noise which will last for about ten seconds at least. Then It will start to whine down, almost like a siren. Then while I'm driving, I will sometimes hear that noise again. But very rarely does it happen when I'm driving. I'm wondering if this is something sirious and if this is something I could fix myself. I would appriciate any help!