Graduation arithmetic

Your backtest of a setup gives expectancy 0.25R and standard deviation 1.2R per trade. (a) How many trades are needed for $t = 2$ in expectation, and for 80% power? (b) After 60 live trades the mean is 0.10R with standard deviation 1.25R. Is this consistent with the backtest at the ±2 SE level? Is it significant on its own? (c) You paper-traded 8 candidate setups, none of which has an edge, and kept the best. With a per-setup false-positive rate of 2.4%, what is the chance at least one "graduated"?