What do cocaine, amphetamines, caffeine, nicotine, and MDMA (ecstasy) all have in common? Select one:

a.
They all increase the activity of the nervous system.

b.
They all cause hallucinations.

c.
They are all taken by people who want to relax or go to sleep.

d.
They are all very highly addictive both physically and psychologically.

why is arctic sea ice important? arctic sea ice keeps the polar regions cool and moderate global climate. sea ice has a bright surface; 80 percent of the sunlight that strikes it is reflected back into space. as sea ice melts in the summer, it exposes the dark ocean surface.

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.

the answer is b. dilution