at the synaptic knob, voltage-gated channels open, thereby stimulating the synaptic vesicles to release their neurotransmitters by exocytosis.

Ireally don’t know

The upward force acting on the wing of a airplane in flight is known as the "lift" force. (d)

The boat's velocity relative to the riverbank can be resolved into two components. the component going north is 2.7 m/s and the component going west is 1.2 m/s.we add these two vectors and then find the magnitude of the resultant to get the speed.the magnitude of the resultant vector from adding can be obtained by the pythagorean theorem.    to two significant figures, the boat's speed relative to the riverbank is 3.0 m/s.