police officer's will allow between 9 and 15 km's over; a small number of driver's will flash their headlights

-- "How to Avoid a Speeding Ticket" on Yahoo! Canada Autos on April 21, 2009

When writing a plural word, you do not add an apostrophe before the S, so in the first image police officer's should be police officers. While km's is tricky, because kms just doesn't look right, one could write either kilometres or KMs.

In the second image, the writer correctly wrote the plural drivers, but then for some reason wrote driver's two sentences later. Driver's is only correct when writing about something possessed by the driver, as in driver's seat.