17) Using truth-tables, check the veracity of the following statement: [0,5pts] : ((rt)(st))(tr)) is equivalent to (t(sr)) [T/F] 18) Using truth-tables, check the veracity of the following statement: [0,5pts] : ((rt)(st))(tr)) is equivalent to (t(sr)) [T/F] 19) Using truth-tables, check the veracity of the following statement: [0,5pts] : ((rt)(st))(tr)) is not equivalent to ((rt)(st))(tr)) [T/F]