Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

What does this below rebus puzzle mean?

What goes through cities and fields, but never moves?

A chicken farmer has figured out that a hen and a half can lay an egg and a half in a day and a half. How many hens does the farmer need to produce one dozen eggs in six days?

Rose, Lily and Jasmine decided to buy flowers for their moms on Mother's Day. One of them bought lilies, the other roses, and the third one jasmines.
'It's funny!' said the girl with roses, 'we bought roses, jasmines and lilies, but none of us bought the flowers matching her name'.
'You're right!', said Lily.
What kind of flowers did each of the girls buy?

A generous owner of a company decided to give a bonus of $45 to every man and $60 to every woman on his birthday. But only one-ninth of the men and one-twelfth of the women were present to take the bonus.

Can you calculate the amount of money the owner spent if there were 3552 employees?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

What are the next two letters in the following series and why?
W A T N T L I T F S _ _

*Hint: Check Puzzle Title

There is a rock group of four men that do not sing. Name It?

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?