A sound wave strikes a student$$s eardrum with a power of $47$ W$.$ The sound$$s intensity at the eardrum is $0\mathrm{.}65$ W$/$m$2$

part a$)$

Assuming a circular eardrum, what is the radius of the student$$s eardrum, in millimeters?

part b$)$

The same sound wave delivers the same power to the eardrum of a second student. His eardrum has a $17\%$ larger radius than that of the first student. What is the intensity of the sound, in watts per square meter, at the second student$$s eardrum?