The basic building block of life is

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

If you let go of the notebook after lifting it, will it move? how?

Which statement describes the formation of our sun? a disk formed of long trails of stars coiled into a spiral. it formed an elliptical flattened disk. heat and gases contracted within a nebula. gravity pushed stars away from a center core.