Discover Questions

Explain the energy changes that occur when a book is held 1 m above the floor and then dropped? If space of the Universe is considered a vacuum how could it expand would it be most likely that its galactic expansion as gravity changes? Show that the derivative of loge sinx/1+sinx when x= pi/4 is 2-sqrt2? Every differential equation of the form
dy/dx=f(y) is separable.? Does anyone know about a Construction Adhesive that can withstand a temperature of -435 F?