What you cannot hold but it is yours?

What runs around the whole yard without moving?

The following sentence is false. The preceding sentence is true.
Are these two sentences true or false?

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

What numbers should go on the bottom line?
3 6 9 15
8 2 10 12
11 8 19 27
19 10 29 39
? ? ? ?

A monk has a very specific ritual for climbing up the steps to the temple. First, he climbs up to the middle step and meditates for 1 minute. Then he climbs up 8 steps and faces east until he hears a bird singing. Then he walks down 12 steps and picks up a pebble. He takes one step up and tosses the pebble over his left shoulder. Now, he walks up the remaining steps three at a time which only takes him 9 paces. How many steps are there?

You have $100 with you and you have to buy 100 balls with it. 100 is the exact figure and you can't go below or above the numbers and you have to use the entire $100. If there is no kind of tax applied how many of each of the following balls will you be able to buy:

Green Balls costing $6
Yellow Balls costing $3
Black Balls costing $0.10

Now, how many of each must you buy to fulfil the condition given?

How do you go from 98 to 720 using just one letter?

How many words can a quill made with the feather of a pigeon write with a 100ml bottle of black ink?

I am a word that begins with the letter “i.” If you add the letter “a” to me, I become a new word with a different meaning, but that sounds exactly the same. What word am I?