Sal estimates lengths using units of inches, feet, centimeters, and meters. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video tutorial, or receive hints.

Practice converting a US customary measure of length to a smaller unit. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

A map from 1868 of the United States showing physical features, mean annual temperatures, rainfall distribution, watersheds, and principal products in the area. The average annual temperatures are shown by isotherms, with temperatures...

Sphinx is a Greek word signifying 'strangler,' applied to certain symbolical forms of Egyptian origin, having the body of a lion, a human or an animal head, and two wings. Various other combinations of animal forms have been called by...

A geo-political map of New Zealand current to 1904, showing major cities, railroad lines, and navigable rivers. Physical features include mountain ranges with elevation measured in feet, major rivers and watersheds, and the 100-fathom...