Hhhhhhhhhhh or HHHHHHHHHHHH both are grammatically correct
Hhhhhhhhhh is a sign of slight exasperation while HHHHHHHHHH is very high levels of frustration.
Units of currency and many exchange
True. These alluvial fans happen commonly in mountainous terrains that eventually lead to flatter plains where water from the stream flows causing the deposits of sediments. Overtime these fans grow and they are called bajada or compound alluvial fans.