9. A point source emits sound waves with a power output of 100 watts. What is the sound level (in dB) at a distance of 10 m? (A)139 (B)119 (C)129 (D)109 (E)10

5. A solid wheel with mass M, radius R, and rotational inertia MR²/2, rolls without sliding on a horizontal surface. A horizontal force F is applied to the axle and the center of mass has an acceleration a. The magnitudes of the applied force F and the frictional force f of the surface, respectively, are: (A)F = Ma, f = 0 (B)F = Ma, f = Ma/2 (C)F = 2Ma, f = Ma (D)F = 2Ma, f = Ma/2 (E)F = 3Ma/2, f = Ma/2

9. A point source emits sound waves with a power output of 100 watts. What is the sound level (in dB) at a distance of 10 m?
(A)139
(B)119
(C)129
(D)109
(E)10

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