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

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

The Federal bank of London is abducted by the robbers. The head of the robbers asked the cashier to empty their money vault to them and when suddenly cashier got a call from her father. To avoid any suspicion, the robber asked the cashier to pick the call and reply her father in the shortest manner possible.

The cashier told her father "Is there an emergency father, Call me when you are free and I will help you in your furnishing" and then the cashier hung up the phone.

After 10 minutes, police arrived at the crime scene.

How did the police know about the robbery?

In the Thar desert, 3 men found a big 24L Jar is full of water. Since there is a shortage of water so they decided to distribute the water among themselves such that they all have equal amounts of it. But they only have a 13L, a 5L and an 11-litre Jar.

How do they do it?

The following alphametic has only one solution. Can you find it?
ENLIST + SILENT + LISTEN = ANAGRAM

PS: You may start the number from 0.

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

How do you go from 98 to 720 using just one letter?

Can you find the thief by just looking at the picture below?

If I put in one canary per cage, I have one bird too many. If I put in two canaries per cage, I have one cage too many. How many cages and canaries do I have?

How can one talk without saying a single word?