Eight prizes are randomly assigned to briefcases with values of $0, $2, $10, $50, $100, $250, $500, and $1000. you select a briefcase at random. what is the expected value of your briefcase?

The square root of 9x plus 7 plus the square rot of 2x equall to 7

Can someone plz me understand how to do these. plz, show work.in exercises 1-4, rewrite the expression in rational exponent form.[tex]\sqrt[4]{625} \sqrt[3]{512} (\sqrt[5]{4} )³ (\sqrt[4]{15} )^{7}\\ (\sqrt[3]{27} )^{2}[/tex]

Someone me! will award brainliest if u explain and answer!