Agirl on the swing throws a ball at the velocity of positive +7.5 m/s relative to the swing. when the ball leaves her hand, the girl has a velocity of +13.5 m/s relative to the ground. what is the velocity of the ball relative to the ground when she throws it?

a. +2 m/s
b.+6 m/s
c.+21 m/s
d. +101.25 m/s

An owl dives toward the ground with a constant velocity of 4.40 m/s at 53.0° below the horizontal. the sun is directly overhead and casts a shadow of the owl directly below it. what is the speed (in m/s) of its shadow on level ground?

Asquare 1m x 1m plate is shown below. all four of its edges are kept at 0 co. at t=0the temperature distribution is given by: y xtsins n75)=.a) using separation of variables determine the temperature distribution t(x,y,t)along the plate at any time t.b) discretize the heat conduction equation +=22222 txtusing a second-order centered difference scheme for the two second derivatives and a first-order forward euler scheme for the first derivative. using von neumann stability analysis, determine the stability criterion for the proposed discretization scheme in terms of , hand t. solve for the maximum allowable time step tmax

What is the role of the water cycle in maintaining freshwater levels in lake and rivers?