Based on relative bond strengths, classify these reactions as endothermic (energy absorbed) or exothermic (energy released):

endothermic
b2+c2--> 2bc
a+bc--> ab+c

exothermic
ab+c--> ac+b
a2+c2--> 2ac
a2+b2--> 2ab

Part a constants huck finn walks at a speed of 0.60 m/s across his raft (that is, he walks perpendicular to the raft's motion what is huck's velocity (speed and direction) relative to the river bank? express your answer to three significant figures and include the appropriate units. relative to the shore)

Which scientist was the first to propose the heliocentric model of the universe? a. aristotle b. isaac newton c. galileo galilei d. nicolaus copernicus

Which of the following best describes the shape of earth's orbit? a.ellipticalb.circularc.spirald.figure eight