Have a Yabba-Dabba-Doo day with Fred Flintstone as he explains how an inclined plane works! Fred shows readers the Flintstone way of using simple machines in ev
Have a Yabba-Dabba-Doo day with Fred Flintstone as he explains how a wedge works! Fred shows readers the Flintstone way of using simple machines in everyday sit
Have a Yabba-Dabba-Doo day with Fred Flintstone as he explains how a pulley works Fred shows readers the Flintstone way of using simple machines in everyday sit