Can someone do 1& 3 and show me?

Which math sentence can be used to determine if the triangle is a right triangle?

Devonte is balancing his checking account. his account statement does not include a deposit of $107.00 that he made on november 1st. what is devonte’s actual account balance?

The power generated by an electrical circuit (in watts) as a function of its current c (in amperes) is modeled by p(c)= -15c(c-8) what current will produce the maximum power?