Decode this picture on T-Shirt and tell what it says ?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

You measure my life in hours
I serve you by expiring
I vanish faster when I am thin
and slower when I am thick
The wind is my energy
What am I?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

Spot 5 differences in two Christmas tree below:

Replace the question mark with the correct number in the below-given picture?

John was running from 40 thieves. John has got 3 gold boxes which weigh as 4kg, 2kg, and 1kg respectively. A witty man asked John to stay with him for seven days in exchange for 1kg gold per day. John needs to stay there for seven days and also do not want to give the witty man any advance. How can John pay for his seven days stay?

Outside a massage parlour, there is a board that reads
"I only massage those who do not massage themselves."

Reading the above statement, does the masseur massage himself?

I am a five-letter word and comprises two different vowels and three same consonants. I am so strong that I can spoil your entire work.

Can you find out who am I?

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