If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

What is the Surname of Barbie Doll?

What has many keys but can’t open a single lock?

I don't get anymore wetter, no matter how much rain falls on me.

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

Can you spot what's wrong with the following sentence?

PETER WAS ANGRY AT
HIMSELF BECAUSE HE
ACCIDENTALLY LEFT THE
THE KEYS TO HIS CAR
AT HIS FRIEND'S HOUSE.

I’m tall when I’m young, and I’m short when I’m old. What am I?

Manish has to secure 40% marks to pass his B.tech final exams.
He got just 40 marks and failed by 40-marks.

What is the maximum marks?

In four steps you need to move the word 'cold' From 'warm' by replacing one alphabet at a time such that every word formed at each step is acceptable in English Dictionary.

I look flat, but I am deep. Hidden realms I shelter. Lives I take, but the food I offer. At times I am beautiful. I can be calm, angry, and turbulent. I have no heart but offer pleasure as well as death. No man can own me, yet I encompass what all men must have. What am I?