A motion where gravity is the only force acting upon it
C. nervous system, because its triggers
The three main layers are the core, the mantle, and the crust. The core is divided into two parts, the liquid outer core, and the solid inner core. Together it is 3450 km thick. The mantle is 2100 km thick, and the crust is 35-70 km thick. Hope I helped!
First the velocity drops to zero in 1.2 secs. In those seconds it went upwards for 7.2 m, then it went from 87.2 to 0m. x-x0=v0*t+1/2*g*t^2 ergo t=sqrt(2x/g) that is 4.1761 s. Finally the total time required is 5.3761 s
Wavelength = speed / frequency
(345 m/s) / (20,000 Hz) = 0.017 m