Bob and caitlyn are playing a trading-card game. between them, they have 81 cards. bob has 7 fewer cards than caitlyn.

Abcd ≅ klmn ≅ pqrs ≅ wxyz given that information, which figures are reflections of abcd?

How are sas and sss used to show that two triangles are congruent?

Find the volume of the solid obtained by rotating the region enclosed by the curves y=1x and y=7^-x about the x-axis. (use symbolic notation and fractions where needed.) volume =