Answer :
The first choice i correct. The second is also correct as it should obey the Law of Conservation of mass. The third choice is incorrect. It depends on the nature of the system. For example, for an ideal gas, you can define at least 2 parameters to set the system boundaries. The fourth choice is incorrect, a system can be theoretical or practical. Hence, the answers are the first and second choices.
Statement 1 and 2 are true about the system.
System
A system can be defined as an interdependent group of items forming a unified whole a number system to act according to the set of rules.
Statement 1 is true about the system. A system can be defined as a group of elements that act as a unit that has been chosen for studying the changes that take place within it in response to varying conditions.
Statement 2 is correct which states the law of conservation of energy. According to the law of conservation of energy, the energy within a system is conserved, it only changes its form.
Statement 3 is not true. The system can be defined in many ways that are totally dependent on the nature of the system.
Statement 4 is incorrect. Systems can be made by humans, but not all systems. A system can be theoretical or practical.
Hence we can conclude that statements 1 and 2 are correct.
To know more about the system, follow the link given below.
https://brainly.com/question/7589753.