Jason was recently hired by a security company to design a new password system for a client. He has come up with 4 different designs. Which of the following should Jason choose, assuming he wants to select the one that is the toughest to crack? A) 5 digit password that uses letters only B) 6 digit password that uses a combination of even numbers from 1-9 and vowels C) 8 digit password that uses the numbers 1-9 D)4 digit password that uses a combination of letters and the numbers 1-9

65 8 7 4 5 6 8 4 3 2 1 9 5 6 4 2 1 6 5 1 5 1 3 2 3 5 multiply the third number in the first row by the seventh number in the third row. add this result to the fifth number in the second row. add to this total ten times the fourth number in the third row. subtract the eighth number in the first row from the result.

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Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?