Questions

It is ABACUS.

Words formed are as below 

BUS
CAB
CUB
US

The function of PAD (Packet Assembler Disassembler) is described in a document known as X.3. The standard protocol has been defined between the terminal and the PAD, called X.28; another standard protocol exists between hte PAD and the network, called X.29. Together, these three recommendations are often called "triple X"

A tetrad is best described by Four chromatids. It is formed from two homologous chromosomes, each consisting of two chromatids in the first stage of meiosis called prophase1.

Culture is the social behavior and norms found in human societies. The 7 main elements that make up culture are ::

1. Social organization
- the family patterns and social classes of a culture.

2. Customs and traditions
- way people act, wear, what they eat, and their laws.

3. Language
- communication by word of mouth.

4. Religion
- a system of beliefs that answers questions about the meaning of life.

5. Art and literature
- ways the people entertain themselves. There stories they tell and how they dance. Its also the music they listen to and there artwork.

6. Forms of government
- the people or group(s) that control the people and provide/ enforce the laws.

7. Economic systems
- the method used by a society to produce and distribute goods and services.