What gas makes up 75% of the earth's atmosphere?

Which describe reflection? check all that apply. light bounces off a boundary.

The rigid beam is supported by the three suspender bars. bars ab and ef are made of aluminum and bar cd is made of steel. if each bar has a cross-sectional area of 450 mm2, determine the maximum value of p if the allowable stress is (σallow)st = 200 mpa for the steel and ( σallow)al = 150 mpa for the aluminum. est = 200 gpa and eal = 70 gpa.

In a given chemical reaction, the energy of the products is greater than the energy of the reactants. which statement is true for this reaction?