Questions

The letter 'X' resembles the same as the tool AXE in sounding.

Hence, the alphabet X is a tool.

Flow control, also called optimized production technology, focuses on the efficient flow of material through the production process. The philosophy of flow control focuses on bottlenecks. For example, an owner using flow control will not buy a machine capable of 1,000 units an hour if supply 500 units. Examine systems and determine where lowest flow is experienced, then address that point and make sure it operates at full capacity. Flow control applies well where maximum productivity is required.

The Length of the Day is determined in Astronomical Units.

The length of a day corresponds to the time the Earth takes to turn around on its axis, which is approximately 24 hours. But it's not exactly 24 hours. 

This phenomenon is due to tides raised by the Moon which slow Earth's rotation. Because of the way the second is defined, the mean length of a day is now about 86 400.002 seconds, and is increasing by about 1.7 milliseconds per century.

Oxford

Chloroplasts use energy from light to transform carbon dioxide and water into sugar and oxygen.

A green pigment located in membranes within the chloroplasts of plants and algae and in the membranes of certain prokaryotes.