I want to understand some concepts

[LuozhuZhang]

I know that the trusted setup requires random numbers and circuits to be used together, and if the random numbers are not random enough or leaked, the entire zkp may have security risks

And I also know that zcash held the powers of tau ceremony in 2017, and more than 90 people participated, and generated this random number (in theory as long as one person deletes the original data, we are safe enough now )

But I want to ask:

1. Why multi-party secure computing can be expanded from six people to more than 90 people, and as long as one of these 90 people deletes the original data, we are safe enough

2. In powersoftau, are we using the public random number they generated at the time and we are enhancing its security every time we use it? This is an interesting question, because I know that during ceremony, someone even ran into a helicopter to generate numbers, in order to prevent themselves from being attacked and eavesdropped, what a crypto world!

3. I see that the initialization of snarkjs needs to use powersoftau, so are we contributing every time we generate random numbers? What is the relationship between these two projects before, or is it just a simple call, if necessary, I can also take a look at the source code myself

All in all, I am deeply attracted by cryptography and look forward to the future that zkp can create, not just privacy and scale

Hope you guys can answer my question or even give me some information for my own research