Question

given reason.............​

Answer 1

The Burj Khalifa height is a staggering 828 meters (2716.5 feet) tall, soaring over Dubai. It's three times as tall as the Eiffel Tower and nearly twice as tall as the Empire State Building. ... Aside from holding the world record for being the tallest building in the world, the Burj Khalifa holds six other world records.

They have base to stand the structure properly

Hope it helps you

Answer 2

Yes , Eiffel tower and Burj Khalifa along with other skyscrapers do have base , they have wide base so that the load of the whole building is exactly at the centre of it so that they don't collapse due to wind or any other natural phenomena( disaster/ disturbance).