A professor writes 40 discrete mathematics true/false questions. Of the statements in these questions, 17 are true. If the questions can be positioned in any order, how many different answer keys are possible?

5. Consider the following: All numbers that end with a zero are divisible by 10. All numbers divisible by10 are divisible by 5. Therefore, every number that ends with a zero is divisible by 5.(a) Is this an argument? Why or why not? (b) Define your variables and write this argument as a sequence of premises in a form of implication,followed by a conclusion. (c) Is this argument valid? Prove using truth tables  and by recognizing the rule of inference