Rainforest are generally defined by two factors chose all that apply The rain must stop during b the year

There must be 69-78 inches of rain per year
There must be 80- 100 inches per year
No rain must be distributed throughout the year

C and D

C. There must be 80- 100 inches per year

D. No rain must be distributed throughout the year ;)

Explanation:

b and c

Explanation:

nanotechnology is a powerful tool in biomaterials research as it creates numerous possibilities for the engineering of functional molecules. nano-bio refers to projected ability to incorporate biomimicry into various materials at nanoscale.  

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.