Find the value of the expression when b= 9 c= 5 and d=10 ½d + c² - b

Arandom sample of 45 observations results in a sample mean of 68. the population standard deviation is known to be 23 a. compute the margin of error at a 959% confidence interval. b. compute the 95% confidence interval for the population mean c. compute the 90% confidence interval for the population mean. d. compute the 75% confidence interval for the population mean

Marcos works the summer while in college and earns $6,000 working on oil rigs. he files his own return, does not take the personal exemption but claims the standard deduction. how much would he pay in income tax?

Which statement is true? a.the graph of a two-variable equation is the set of all points in the coordinate plane that solve the equation.b.the graph of a two-variable equation consists of only two points: one with a zero y-coordinate, (a,0), and one with a zero x-coordinate, (0,b).c.the graph of a two-variable equation is the set of all positive points that solve the equation.d.the graph of a two-variable equation is a single point that solves the equation.