Adolphin emits ultrasound of 100khz and uses the timings of reflection to determine the position of objects in the water. what is the wavelengths of this ultrasound? note the speed of sound in water is 1480m/s.

           Wavelength  =  (speed) / (frequency)

                             =  (1,480 m/s) / (100,000 /s)

                             =      0.0148 meter

                             =         1.48 centimeter

                             =         14.8 millimeters 

Julia would be observing a. static electricity was caused by her sweater rubbing against her shirt and transferring electrons. she didn't touch anything metal, so that would cancel out b.she most likely didn't rub her sweater against her hair either, so that cancels out c.she also didn't scoot across the carpet while trying to take her sweater off, that cancels out d.so that leaves a.a. is correct.