What is the answer to double 7 multiply 3 and 1 and then subtract the second from the first number

Ineed with number 6 , explain how to get 1978

1- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis.2- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in the first question?

Say that a supplier claims they are 99% confident that their products will be in the interval of 50.02 to 50.38. you take samples and find that the 99% confidence interval of what they are sending is 50.00 to 50.36. what conclusion can be made? homework : 5vd. comparing sample confidence intervals with given intervals (links to an external site.)links to an external site. (3: 43) 5dc. confidence intervals in manufacturing, high vs low level of confidence, wide vs narrow (links to an external site.)links to an external site. (docx) the supplier is less accurate than they claimed the supplier products have a lower mean than claimed the supplier is more accurate than they claimed the supplier products have a higher mean than claimed