electron

When the acetate strip is rubbed against the duster, electrons are transferred from the acetate strip to the duster. As a result, the acetate strip loses electrons and becomes positovely charged. The duster gains electrons and thus becomes negatively charged. Notice that protons, because they are bound to nuclei of atoms, are immobile.

Therefore, only statement (1) is correct.
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No. It is not true.

"Rate of radioactive decay" means the number of nuclei that disintegrate in 1 second in a sample of radioactive substance. The radioactive decay rate depends not only on the half life, but most importantly, the number of nucei present in the sample. If the number of nuclei in sample Y is much greater than that of sample X, the decay rate of Y may exceed that of X.

[N.B. More precisely, the decay rate is proportional to the number of nuclei in the sample, and inversely proportional to the half-life. Thus, if the number of nuclie of sample Y is greater than 2 times the number of nuclei in sample X, the decay rate of sample Y exceeds that of sample X. The statement is true if and only if both samle X and sample Y contain the same number of nuclei. It is thus not a "generally true" statement.]

Well, the answer (2) is some kind of impossible. And if the duster becomes possitively charged, then, the acetate strip won't becomes possitively charged, and therefore, the answer is A

hope that i have helped you.