The depth of the water at the end of a pier changes periodically along with the movement of tides. On a particular day, low tides occur at 12:00 am and 12:30 pm, with a depth of 2. 5 m, while high tides occur at 6:15 am and 6:45 pm, with a depth of 5. 5 m. Let t = 0 be 12:00 am. Which periodic function, sine or cosine, would be a simpler model for the situation? Explain.

Simonne used the following steps to simplify the given expression. 12-3(-2x+4) step 1: 12+(-)+(-3)(4) step 2: 12+6x+(-12) step 3: 12+(-12)+6x step 4: 0+6x step 5: 6x what property of real numbers was used to transition from step 3 to step 4? •identity property of addition •inverse property of addition •associative property of addition •commutative property of addition