At the instant shown in Figure 3, the blocks are moving toward each other with the same speed of 0.35 m/s. The blocks collide 0.50 seconds later. What is the speed of the two=block system's center of mass just before the blocks collide?

Which best describes how fluids change as they travel through different portions of the convection currents? they change to solids at the outer portion of the convection currents. they change to solids at the inner portion of the convection currents. they become more dense at the outer portion of the convection currents. they become more dense at the inner portion of the convection currents