Indicators meaning gas, thermostat, and speed,

My radio comes on but no sound new system put in

White smoke is coming from the exhaust when I go on an incline. Check Engine light came on and car ran rough.

What is the cost to replace a glove box in a 2002 C320 Mercedes Benz?

The problem occurred after the battery was changed.

I was driving then I went to use the cruise control once I did that the car worked with the cruise control. The next morning I start the car and it was idling at 40 rpm while in park position. Now it remains idled all the time. Any answers?