Q$9.$ Answer the following questions about Cryptomining:

$($a$)$ Explain the mining process.

$($b$)$ What is a hashrate? What is it used for?

$($c$)$ The target hash of some cryptocurrency starts in $16$ hex zero digits followed by $7$A$.$ Compute the network difficulty if the initial target hash had $8$ hex zero digits and the rest of the bits are ones.

$($d$)$ What is a mining pool? Why miners join mining pools? Give two examples of mining pools for Bitcoin and two for Ethereum.