In table tennis a player serves 2 times before the other player serves.

What is the best way to teach common sense to a child?

When dealing with your guest how you say something is as important as what you say true or false

Ascientist introduced mutations in a gene sequence isolated from bacteria. study the sequence, and identify the steps where the mutations may affect the formation of proteins. in the sequence, black letters stand for protein coding regions and red letters stand for noncoding regions.