Geostrophic wind a) is slower than surface winds b) depends on friction c) flows from high pressure to low pressure d) flows parallel to contour lines of upper-air pressure

Geostrophic wind D) flows parallel to contour lines of upper-air pressure .

Explanation:

Geostrophic wind -

Air parcel generally moves from higher pressure to lower pressure due to pressure gradient force and left or right deflection due to coriolis force. When this deflection takes place a time comes when pressure gradient force and coriolis force becomes equal and the air parcel moves parallel to isobar then the winds are called geostrophic winds .

heat from the core of the earth causes convection currents to occur in the mantle. these currents slowly move the crust around.