1. Define the term 'mission' (like the Alamo). 2. Define the term 'secede'.

3. Define the term 'reservation' (relating to Native Americans).

1. An objective that must be completed.

2. Secede means to break away from something or someone.

3. An area of land set aside for occupation by North American Indians or Australian Aboriginal people.

Explanation:

the answer would be the third option, "no, ariel should have added 9^2 and 12^2 and compared that to 15^2."

this is found through the pythagorean theorem, which is a^2 + b^2 = c^2.

this is the correct way of solving the problem:

9^2 + 12^2 = 15^2

81 + 144 = 225

225 = 225