[填空题]
If two firecrackers produce a sound level ot4+8vm b. gxq;rtv1ne f 95 dB when firei b v 4s5xq7a9q.v3ixud simultaneously at a certain place, what will be the sound level if only one is exploded? sva qxi7x 39i5b4uqv.[Hint: Add intensities, not dB’s.] dB
