Q1: How to chain these two conditions making them if BOTH A AND B, then proceed...
Q2: How to make them stick for
You can't do it that way. You have to either repeat your RewriteConds or rethink your rewrite rule using references to do it all in one rule. The first route, though not pretty, would be the easiest. so
RewriteCond A
RewriteCond B
RewriteRule 1
RewriteCond A #duplicate
RewriteCond B #duplicate
RewriteRule 2