North america experienced all of the following during the last glacial period except alpine glaciers covered the rocky and cascade mountains. sea level was at least 100 m lower than it is today. coastlines were extended. the hudson bay was covered with alpine glaciers.

the Hudson Bay was covered with alpine glaciers

Explanation:

During the last glacial period, large portions of North America were covered with ice. The majority of the ice was from the ice sheets that were covering Canada and the northern part of the United States, and the alpine glaciers on the mountain ranges. Hudson Bay was all frozen at this point of time. It was not covered with alpine glaciers though, instead it was covered with the ice of the extended ice sheets, with the ice cover reaching up to 2 km in thickness.

+15-35=-20

going in opposite directions