diff --git a/FSF-2020/integrals-of-multivariable-functions/SurfacesAnimation.mp4 b/FSF-2020/integrals-of-multivariable-functions/SurfacesAnimation.mp4 deleted file mode 100644 index 181615db..00000000 Binary files a/FSF-2020/integrals-of-multivariable-functions/SurfacesAnimation.mp4 and /dev/null differ diff --git a/FSF-2020/integrals-of-multivariable-functions/area_Under_func.gif b/FSF-2020/integrals-of-multivariable-functions/area_Under_func.gif new file mode 100644 index 00000000..223218b9 Binary files /dev/null and b/FSF-2020/integrals-of-multivariable-functions/area_Under_func.gif differ diff --git a/FSF-2020/integrals-of-multivariable-functions/area_under_func.mp4 b/FSF-2020/integrals-of-multivariable-functions/area_under_func.mp4 deleted file mode 100644 index 7072672e..00000000 Binary files a/FSF-2020/integrals-of-multivariable-functions/area_under_func.mp4 and /dev/null differ diff --git a/FSF-2020/integrals-of-multivariable-functions/elementary_area.gif b/FSF-2020/integrals-of-multivariable-functions/elementary_area.gif new file mode 100644 index 00000000..5c9ac03c Binary files /dev/null and b/FSF-2020/integrals-of-multivariable-functions/elementary_area.gif differ diff --git a/FSF-2020/integrals-of-multivariable-functions/elementary_area.mp4 b/FSF-2020/integrals-of-multivariable-functions/elementary_area.mp4 deleted file mode 100644 index 601a56af..00000000 Binary files a/FSF-2020/integrals-of-multivariable-functions/elementary_area.mp4 and /dev/null differ diff --git a/FSF-2020/integrals-of-multivariable-functions/non_rect_region.gif b/FSF-2020/integrals-of-multivariable-functions/non_rect_region.gif new file mode 100644 index 00000000..c8e7c8cd Binary files /dev/null and b/FSF-2020/integrals-of-multivariable-functions/non_rect_region.gif differ diff --git a/FSF-2020/integrals-of-multivariable-functions/non_rect_region.mp4 b/FSF-2020/integrals-of-multivariable-functions/non_rect_region.mp4 deleted file mode 100644 index 2eebc65f..00000000 Binary files a/FSF-2020/integrals-of-multivariable-functions/non_rect_region.mp4 and /dev/null differ diff --git a/FSF-2020/integrals-of-multivariable-functions/surface.gif b/FSF-2020/integrals-of-multivariable-functions/surface.gif new file mode 100644 index 00000000..ae23a7bf Binary files /dev/null and b/FSF-2020/integrals-of-multivariable-functions/surface.gif differ diff --git a/FSF-2020/integrals-of-multivariable-functions/YlimitXdependent.gif b/FSF-2020/integrals-of-multivariable-functions/y_limit_dependent_on_x.gif similarity index 100% rename from FSF-2020/integrals-of-multivariable-functions/YlimitXdependent.gif rename to FSF-2020/integrals-of-multivariable-functions/y_limit_dependent_on_x.gif