Answer: In an ordinary year, if you were to count all the days in a calendar from January to December, you'd count 365 days. But approximately every four years, February has 29 days instead of 28. So, there are 366 days in the year. This is called a leap year.
Step-by-step explanation:
It would help the chain run smoother and work better and faster.
The answer is the fourth one. Trust me I had the same question
If Nate paints the wall in 4 hours, it means that he can paint 1/4 of the wall every hour.
Similarly, if Jill paints the wall in 7 hours, it means that he can paint 1/7 of the wall in one hour.
So, together, they paint the following fraction of the wall in one hour:
.
At this rate, they need 28/11 hours to paint the whole wall, in fact, after that amount of time they paint

i.e. the whole wall