Final answer:
Elena will take 75 seconds to fill 10 bottles with water.
Step-by-step explanation:
To find the time it takes Elena to fill 10 bottles with water, we need to divide the total volume of water by her constant speed. Elena fills bottles at a speed of 2 ounces per second and each bottle has a capacity of 15 ounces. To fill 10 bottles, we will need a total of 10 * 15 = 150 ounces of water. Dividing this by the speed of 2 ounces per second, we get 150 / 2 = 75 seconds. Therefore, it will take Elena 75 seconds to fill 10 bottles with water.
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