HI Rohit,
We would need few more information to guide you through..
From where are you trying to ping 3750? Do you have topology diagram how this is connected?
Regarding the internet, may be the clients are not getting the dns ip address or dns currently configured is not working. Please try to set a public dns 4.2.2.2 for testing and check if urls are working.
Hope that helps.
Regards
Najaf
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