Nothing. There are no alligators in the ocean.

The woman had committed a murder and was determined to be guilty. A judge called her name, gave her the death penalty, and then two bailiffs escorted her out of the courtroom. Years later she is executed while under the care and supervision of a doctor and detention officers.

4

Neither—they both weigh a ton.

A Woman.

Because the riddle asks who is the last man but not at all women. Hence, the Last Man On Earth Received A Phone Call from a woman.

60. 100 years in a century, 365 days in a year, 24 hours in a day, 60 minutes in an hour, & 60 seconds in a minute.

Mosquito.

Nine

You have to ask either one of them "Which door would the other one say is the right one?"

Then they both point to one door. The liar points to the wrong door because he does the opposite of the truth, and the truth speaking one will point to the wrong door because he will point to the wrong door.

The age of the twins would be 5 years each. And the age of the Eldest sister is 7 years.

A clock.

A yardstick.