The second answer is not a characteristic because compounds don’t vary from sample to sample. For example NaCl (table salt) is indistinguishable from sample to sample.
Answer:
B. only particle Z
Explanation:
In the case of subatomic particles, those positive and neutral are located in the nucleus, and those with a negative charge on the outside.
Timbuktu was considered a MASSIVE trade center in Mali. That is how all of the foreign goods came into the kingdom. It also had education centers which was very important in Mali.