How do some people end up crazy and some of the things that make people crazy make others stronger

What is thought to have caused the mass extinction at the end of the cretaceous period?

Aflashlight battery is an example of a) potential energy b) kinetic energy c) thermal energy d) solar energy

The fascicles of the deltoid are ; the fascicles of the pectoralis parallel; bipennate fusiform; unipennate multipennate; triangular bipennate; fusiform