How far have humans been able to drill into the earth crust ? Can someone plz help me

What volume of a 0.25 m solution can be made using 0.55 moles of ca(oh)2

Apopulation of black bears depends on salmon from a stream for food. if a drought causes the stream to run dry one year, how will this likely impact the black bear population?

The nervous system interacts with the endocrine system by a. using hormones as connections b. sending nerve impulses directly to glands c. using neuroendocrine cells as connections d. sending neurotransmitters directly to neurons