Answer:
26036485.6433 W/m²
Explanation:
E= Energy = 470 J
t = Time = 4 seconds
d = Diameter = 2.6 mm
Power is given by

Intensity is given by

The intensity of the laser beam is 26036485.6433 W/m²
When someone lifts a book from the ground, the work you use is positive. By lifting the book, you change it's energy and it's original place The book gains, kinectic energy.
Hope I helped.