Answer: Separately derived system
Explanation: A separately derived system is used to describe a premise wiring system whose power is derived from a source of electrical energy such as transformer, solar photovoltaic cell or generator. A separately derived system has no direct connection to any conductor from another system or doesn't generate it's power from any direct connection to a conductor from another system or source except those from established from bonding or grounding connections. Separately derived systems usually generate it's power on it's own.
The beginning development of a
star is marked by a supernova explosion, with the gases present in the nebula
being forced to scatter. As the star shrinks, radiation of the surface increases
and create pressure on the outside shell to push it away and forming a
planetary nebula or white dwarf.
Answer:
The correct answer is d Both the observer's are correct
Explanation:
We know by postulates of relativity that laws of physics are same in different inertial frames.
Thus for each of the frames they make observations related to their frames and since the observations are true for their individual frames they both are correct. But when we compare the two frames we need to use transformation equations to compare both the results.
Here we have mass that moves at ceratin speed. This means that we have momentum. The law that must be observed is law of conservation of momentum. It states that momentum before certain event is equal to a momentum after that event. Here we have three masses so we can write this as:

Before the firecracker blows a coconut does not move, so left side is equal to 0:

We know that m1=m2=m and m3=2m. Also we are asked to find v3f so we can rewrite formula:

We must take in consideration that two parts with same mass do not move in same direction. The center of mass of these two parts moves between them at angle of 45° with respect to both south and west. The speed of a center of mass is:

This speed we can insert into formula for v3f:

We can see that part of a coconut with biggest mass has same speed as center of mass of two other parts. Negative sign shows that direction is opposite to direction of two pats. Biggest part moves towards north-east.