At a distance of 20 m from a source of sound, the sound level is 40 db. if the observer backs up to a distance of 40 m from the source, what will the sound level be? o a. 34 db o b. 28 db ° c. 20 db o d. 10 db

The sound level is 34 dB.

(A) is correct option.

Explanation:

Given that,

Distance from a source of sound

Sound level

Distance from a source of sound

We need to calculate the sound level

Using equation

Hence, The sound level is 34 dB.

answer: i think he can see forward ten seconds and move forward ten seconds but giorno can undo his actions with ger.

explanation:

explanation:

v=uf/(u-f)

= 5.-10/(5+10) convex lens has negative focal length