Please i really need help fast Determine whether the systems of natural numbers, integers, rational numbers, irrational numbers, and real numbers are closed or not closed for addition, subtraction, multiplication, and division. Type your response here:​

Explain how you can use the associative property to evaluate (7x50)x4.

Thompson and thompson is a steel bolts manufacturing company. their current steel bolts have a mean diameter of 127 millimeters, and a variance of 36. if a random sample of 35 steel bolts is selected, what is the probability that the sample mean would differ from the population mean by greater than 0.5 millimeters? round your answer to four decimal places.

You have 138.72 in your saving account u take out 45.23 and 18.00 you deposit 75.85 into your account