Two successful inventions during the Tang era

Doctors recommend that both men and women take an aspirin every day to prevent heart attacks. however, the sample in the research study only contained men. the problem with doctors making this aspirin recommendation reflects a bias.

Children begin to use tools at about what age? a. 18 months b. 2 years c. 1 year d. 6 months

The physical feature that makes up part of the border between canada and the united states is the