What needs to be emphasized in this step when reading?
"Turn the two-bottle assembly over, and place the assembly on a table with the filled bottle on top. Watch the water slowly drip down into the lower bottle.... Now, rapidly rotate the bottles in a horizontal circle a few times. Observe the formation of a funnel-shaped vortex..."
a.
rapidly rotate the bottles in a horizontal circle
c.
both A and B
b.
Watch the water
d.
neither A nor B
Please select the best answer from the choices provided
These two parts of the instruction(s) are relatively important and need to be paid attention to, so to put stress on and emphasise these would only make sense!
