Answer:
We see an object when light falls on it and gets reflected from its surface and enters our eyes. In a dark room, there is no source of light. no light falls on the surface of objects and we do not see them. This is why we cannot see the objects in a dark room.
You can earn ranks! That is important.
Let's say for example that the business is taking in $2000 of revenue. That is the amount that the business collected for it's services - like for fixing the computer. What if though it costs $500 for the equipment (that's an expense). Now they only made $1500. Now the customer complains and says that the computer isn't fixed properly so the company sends out a techie for 2 additional hours. They need to pay their employee (another expense). Now the $1500 is down to $1400. They would have utilities to keep their lights on and insurance and many other expenses.
Your profit looks like this:
Profit = Revenue - Expenses
