The tectonic and rock cycles recycle the lithosphere. the tectonic cycle includes the processes of seafloor spreading, subduction, and mantle convection. the rock cycle includes the processes of
a. weathering, sedimentation, and assimilation
b. erosion, condensation, nitrification, and tectonic activity
c. weathering, erosion, sedimentation, and metamorphism

The Rock Cycle is a group of changes. Igneous rock can change into sedimentary rock or into metamorphic rock. Sedimentary rock can change into metamorphic rock or into igneous rock. Metamorphic rock can change into igneous or sedimentary rock. Igneous rock forms when magma cools and makes crystals.

So the answer is C

object 2 because all the other ones are wrong

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s