DB Encoding, and Charset Declaration

Dear Sir,

I have db encoding enabled as per bellow in my config - settings.php file:

 * @global string $CONFIG->dbencoding
$CONFIG->dbencoding = 'utf8mb4';

I have two questions:

Q1. Should Tables and Column (Collations) be set to = "utf8mb4_general_ci" or it should be "utf8mb4_unicode_ci"?
Q2. Should I declare chareset in .htaccess as AddCharset UTF-8 .utf8 ?

I would really appreciate a kind answer.