You can use PFD approved device styles 2-5, I'm pretty sure
Since you don't ski over water, you don't need one.
No...
Type, I, II, or III PFD
when on board a ski boat that is underway
There isn't a maximum or minimum height you need to be.
Washing your PFD with soap and cold water could cause it to wear out.
The elements, sun, water, and age can cause a PFD to wear out over time.
Personal flotation device (PFD) are stored onboard depending on the size of the boat. Anyone in the boat should wear a PFD - sailing dinghy, rowing boat, jet ski, canoe, and wind surfing.
This can be caused by a weak coil in the ski, when the ski is in the water, it is under load and can refuse to start, even though it might run fine on a trailer. You will need a replacement coil.
i think no because it is a sport which almost anyone can do
yes
A Type I PFD will turn MOST people face up.