Can you place three balls such that the equation shown in the picture holds true?

John was visiting his friend Jacob. He found out that his friend's wife had just killed a burglar in self-defense.
John asks Jacob about what happened and he told that "His wife was watching television when suddenly the bell rang. She thought that it is her husband Jacob but she found the burglar who attacked her instantly and she got so frightened that she killed the burglar immediately with the knife.
John asked the police to arrest his friend's wife. Why?

In which direction should the missing arrow point?

John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?

If we change the South-East direction into North and North-East into West and all others similarly.
Can you find out which direction will be in the place of South-West direction?

What word begins and ends with an E, but has only one letter?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

What seven-letter word has hundreds of letters in it?

With the help clues provided in the image, can you find the 5 digit key?

You’ll find me on Mercury, Earth, Mars, Jupiter, Saturn, and Uranus. But never Neptune, or Venus. What am I?