Mary has a dilemma. she has a contract to buy her mother’s house when her mother is finally ready to move to a senior living community. but now mary has to move because of work and no longer wants to buy the house. with their mother's agreement, her sister tina steps in to replace mary, releasing mary from her obligation. they write up a new contract, with the only change being that tina is now the party to the contract rather than mary. this is an example of

Novation

Explanation:

                A Novation in a contract law or in  any business law means to give the right of one party's obligation to the obligation of another party with the previous party's consent. It means replacing a party in a contract with a new party after the previous party has given her consent of replacement. The new party becomes the rightful owner of the contract and is responsible to the obligations.

               In the given context, there is an novation agreement between Mary and Tina, when Tina replaces Mary with the obligations in the contract with the prior consent from to Mary as Mary has to move to other place because of work and does not wants to buy the house.

Hence the answer is --

Novation

we can solve this via the kinematic equation:

where the vertical velocity is zero and so:

since the height of the building is 29.3 meters then:

the ball was in motion for approximately 2.45 seconds