hi, i am haveing some trouble with these two problems any help with them would be great.

1)
A loudspeaker is placed between two observers who are 180 m apart, along the line connecting them. If one observer (observer A) records a sound level of 55 dB and the other (observer B) records a sound level of 70 dB, how far is the speaker from each observer?
(from observer A)
(from observer B)

this would be easy if they were to give me the average power that the waves generate, but they dont and as a result i am stuck on it.

2)
A fireworks rocket explodes at a height of 100 m above the ground. An observer on the ground directly under the explosion experiences an average sound intensity of 7.25 10-2 W/m2 for 0.205 s.
(a) What is the total sound energy of the explosion?
kJ
(b) What is the sound level in decibels heard by the observer?
dB
thanks for your help
matt