A. 5×20
x=100
check
100/5=20
20=20
b. 15=30/2
×2. ×2
30=30.
check.
30/2=15
15=15
Hope this helps..
Answer is A: Mongol made up the ruling class of the Yuan Dynasty
The limits that human remains such as skeletons have as sources of historical information are:
- Physical condition of the bones; usually the older, the more fragile and more difficult to study.
- The completeness of the skeleton. Usually, skeletons are found incomplete for a number of reasons (anticipated decay of some bones, scavenging animals taking several bones away, etc.) and the more complete, the better.
- The information that can be extracted from bones usually limits to: a) the dead person's physical features (height, physical build, gender, etc.); b) evidence of several diseases and/or trauma (injuries breaking bones), c) facial traits (through skull forensic reconstruction) and d) racial group, diet, evidence of toxins through study of he teeth.
