Bull Call Spread: (Long 50/Short 60)
50 Call = $5 ($500)
60 Call = $2 ($200)
Cost of Trade = $3 ($300)
Max Profit = $7 ($700)
Max Profit = 60-50=10 minus cost of trade (3) = 7
***In your examples, "net profit" = "max profit", depending upon your definition of "max profit".