In order for you to see an object, which of these must happen? a) light reflected from the object's surface must enter your eyes. b) the object must have a shadow, for your brain to interpret what it is. c) light must be absorbed by the object and then refracted back to your eyes. d) light travels from the object, back to the light source, and then to your eyes.

Why are people not able to skip a dive to the deepest part of the ocean

)benzene and toluene form nearly ideal solutions. consider an equimolar solution of benzene and toluene. at 20 °c the vapour pressures of pure benzene and toluene are 9.9 kpa and 2.9 kpa, respectively. the solution is boiled by reducing the external pressure below the vapour pressure. calculate (i) the pressure when boiling begins, (ii) the composition of each component in the vapour, and (iii) the vapour pressure when only a few drops of liquid remain. assume that the rate of vaporization is low enough for the temperature to remain constant at 20 °c.

Acetylene gas c2h2 undergoes combustion to produce carbon dioxide and water vapor how many grams of water are produced by the same amount of c2h2?