UIUC MS ECE

Have some queries regarding UIUC MS ECE ...

1. Is contacting a PI needed, or have people gotten admits without establishing a connection with a PI?
2. Do they differentiate in evaluating MS and PhD candidates given that their masters is a feeder into their PhD?
3. What is the typical cohort size for MS ECE?
4. Is it true that most of their admits are for people who have done their undergrad at UIUC?
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