Are the apostrophe placements correct in every example?
• two weeks' vacation • four days' personal time • three months' sabbatical time • ten nights' accommodations • three hours' sleep • eight months' pregnancy • eight months pregnant • five minutes' time • a penny's worth • two pennies' worth • a nickel's worth • two nickels' worth • a dollar's worth • five dollars' worth • two seconds' time • five years' probation
Thank you kindly.