Q$2.$ Answer the following questions about Ethereum:

$($a$)$ What programming languages are used to implement EVM?

$($b$)$ What programming languages are used to write Ethereum smart contracts?

$($c$)$ What is the advantage of using Ethash in Ethereum proof of work?

$($d$)$ What alternative of proof of work is proposed for Ethereum $2\mathrm{.}0?$