To prove that a given quadrilateral is a parallelogram, it is enough to show that:
both pairs of opposite sides are parallel.
the diagonals intersect each other.
pairs of adjacent sides are congruent.
all interior angles are right angles.
the diagonals are perpendicular bisectors of one another.

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