All right! And when that impetus reduces,
motion also reduces.
When the impetus is
removed, the object
stops moving!

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.

answerleaving cheese out to get moldy;