How do you get the Solana platform tools version? Or the `rustc` version used by Solana to compile programs?

When building a Solana rust program, it does NOT use your normal system's rust compiler (rustc), instead cargo build-sbf uses the Solana "platform tools" under the hood which ships a separate version of rustc which is used to actually compile Solana programs.

1. How can you find the version of the platform tools your system will use?
2. How can you find the rustc version your program will be compiled with?

My current Solana/Agave CLI version is:

solana --version# output: solana-cli 2.0.0 (src:16de8b75; feat:4288794394, client:Agave)

And my current system's rustc version:

rustc --version# output: rustc 1.78.0 (9b00956e5 2024-04-29)