Short tricky riddles

Tommy Tucker took two strings and tied two turtles to two tall trees. How many T’s in that?

I am the beginning of the end, and the end of time and space. I am essential to creation, and I surround every place.

What starts with a 't' ends with a 't' and is full of 't' ?

What kind of dog has a bark but no bite?

Can a man legally marry his widow's sister in the state of California?

There is bomb on top of a computer; around the computer are a hairbrush, keys, phone and a cup. When the explosion comes, what item destroyed first?

Imagine you are in a sinking rowboat surrounded by sharks. How would you survive?

If it takes one man three days to dig a hole, how long does it take two men to dig half a hole?

What am I?

There was a plane crash every single person died. Who survived?