You can only be employed under the terms of the L-1 visa petition.

I am on a L1 Visa in USA. Can I invest in a C-Corp and become a stakeholder?

Passive investment is permissible and should not violate status.

How do I get proof of my mom entering the US and how much? Thanks

She needs to file a Form I-102 to obtain a duplicate arrival record.

Is an F1 visa valid only with a state or throughout the US

No, but you will have to file for a change of schools with a new I-20 to maintain your status.

Can I have multipe freelance/part time position at the same time while I'm on Cpt status?

No. You should only be working under the terms of the CPT.

You can retain the priority date on a subsequently filed I-140 in these circumstances.

What happened to my mother's green card?

The green card should arrive within a couple of months of arrival. if it does not, your mother may want to file an I-90.

Hi I was selected for 2015AS000080**, and I would like to know about my chances of being informed for an interview.

You must follow the Visa Bulletin each month and hope that the number advances in time tile adjust status before the end of the fiscal year.

My H1B visa extension is in process. Can I move to a new job while my extension is in process?

You would have to have the new employer file a petition for a change of status on your behalf prior to making any move.

Can H1b cap-exempt petition by new employer be filed for 3 year validity based on previous H1b I-797 approval of only 1 year ?

The 221g issue will not go away, even if the new petition is filed.