PIE six and seven: questions

From: Joao S. Lopes
Message: 71552
Date: 2013-11-11

1) PIE *swek^s. How to explain the anomalies and different forms? Why *swek^s /*sek^s/ *wek^s/*k^swek^s/*uk^s? Why Sanskrit s.as., instead of expected *saks.- or *svaks, ? What is it relationship to Semitic shish-?  *swek^s- > *sek^s after influence of *septm sounds plausible.
2) PIE *septm . It's obviously related to Semitic *sabatum, but... where did the contact occur? Do similar vocalism in *septm *dek^mt *h1newn point to an analogous formation?

Joao S. Lopes
Rio, Brazil