Answer:
Power, P=1.57×
Watt
Step-by-step explanation:
Given
Intensity, I=1×
W/m²
Distance, r=5 meter
Considering the hemispherical space with radius 5 meter centered on the speaker. Speaker emits sound wave continuously with Power P. Intensity I is constant throughout the space and defined as power per unit area.
I=

so, P=I×A
where A is the area of shape of propagation.
since ,shape of propagation is hemispherical
so, A=2×p×r²=2×3.14×5×5=157 m²
P=1×
×157
P=1.57×
Watt