Well windspeed is in the senter of the wind
instrument and it is in Knots,
Boat speed is seen lower part of the first instrument and also in SOG on the Plotter.
To put the Parasailor up and take it down in low winds you can do it alone easy. stronger winds can be done alone also but will need a bit of training and a nice step by step way to do it.
But normally its me and wife and then it is very easy.
if you just plan on how to do it, and train on it adjust, then you can do many things
her is a film of a singelhanded sailor showing how he takes down his spinnaker
while sailing alone. and this is a fast mono. Elan 350 and he is speaking norwegian