To determine if the robot meets both of Nadia's expectations, we need to evaluate the inequalities based on the given values for \( A \) (air) and \( W \) (water).
Nadia's expectations are expressed in two inequalities:
- \( 12A + 8W > 343 \) (to filter more than 343 liters)
- \( 3A + 4W < 49 \) (to use less than 49 Joules of energy)
We will substitute \( A = 20 \) minutes and \( W = 15 \) minutes into the inequalities.
First Inequality: \[ 12A + 8W > 343 \] Substituting \( A = 20 \) and \( W = 15 \): \[ 12(20) + 8(15) > 343 \] \[ 240 + 120 > 343 \] \[ 360 > 343 \quad \text{(True)} \]
The first inequality is satisfied.
Second Inequality: \[ 3A + 4W < 49 \] Substituting \( A = 20 \) and \( W = 15 \): \[ 3(20) + 4(15) < 49 \] \[ 60 + 60 < 49 \] \[ 120 < 49 \quad \text{(False)} \]
The second inequality is not satisfied.
Based on this evaluation, the robot meets the first expectation (amount of air and water filtered), but it doesn't meet the second expectation (energy used).
Thus, the correct answer is:
(Choice B) The robot filters the expected amount of air and water, but it doesn't use the expected amount of energy.