When did the universe start according to the big bang theory

What is thought to have caused the mass extinction at the end of the cretaceous period?

Nasa scientists must work together to make sure that everything is correct and accounted for when launching a shuttle. besides a physicist, what other type of scientist would be in making sure that the shuttle has the appropriate type and amount of fuel to reach its destination?

The pressurized plants and fungi mentioned in the video have some surprising similarities. what differences would you expect them to have?