identify a spacecraft operated by human beings and describe how it helped add to our knowledge of space

Determine the age of a fossil if it had only one eighth of its original carbon-14 content remaining?

What changes occur in the brain during the teenage years? 25 points, someone me out!a.) thinking becomes slower as the brain grows larger. b.) connections between neurons become stronger and faster. c.) unused neurons fuse together to form larger, better functioning neurons. d.) more neurons are developed.

What is the speed of an object at a given moment?