Explanation:
Average speed = distance / time
|v| = (7 km + 2 km) / (2 hr + 1 hr)
|v| = 3 km/hr
Average velocity = displacement / time
v = (7 km east + 2 km east) / (2 hr + 1 hr)
v = 3 km/hr east
Look it up on google it has the answer
I would say the last option, since with an increase in temperature, water molecules will speed up.
The layers form from sand dunes