I am coming to USA first time and have few questions in mind:

1) What to enter in declaration form in india. I have a High end mobile tablet, good camera, do i need to enter the details in the form or is it fine, since when i come back i don't want things to get difficult?

2) I have to change flights at NEWARK LIBERTY airport for SFO. Now will my port of entry be newark or sfo? How to go about changing? Is it like just go for domestic change or what? Can anyone explain?

3) Also how many hours before, for each departure from india and departure from usa, should i arrive at the airport so i dont have to hassle?

4) I have exchanged currency, but they were only having 100$ bills. So can i know what's the best way to get change, that is in smaller denominations like 1$, 2$ etc. Can we change at airport with/without expenses or buy something and get the change?

5) The exchanger has put some sort of small stamp at back of the 100$ bill, is it normal and fine?

6) For i94 form: What to enter here? 10. Mark an X in the Yes or No box. Are you traveling on a business (work-related) trip?

I am on b1/b2 visa but i am not for exact business. I have been chosen to attend a summit and i am a student. After that i will roam around for 2 days. So what to enter there?

7) Also i would get only 1:30hrs in between my flight for SFO, will i be able to clear everything in that time or anything else that i need to know?

8)If that time is small, and if i miss the connecting flight, how to overcome that situation? Who will arrange my next flight?

9)Also while exiting US, i have the reverse pattern from SFO-NEWARK-INDIA in that case what will be my exit point and where i have to submit the i-94 form, sfo or newark. And at sfo, do i need to go for domestic departure or international?

Airlines : United Airlines