
A pre-flight check should be executed...
Before you take off, you should check at least these things: pilot, lines, canopy, wind, airspace.

What do you do when you can't hear the instructor over the radio during a flight?
B is correct, A and C are nonsense of course.
Answer D is the second best choice in case your mind goes blank, you panic and you don't know what to do. It's better to do nothing in that case.

What do we call the risers that are connected to the lines running to the leading edge of the canopy?
These are the A-risers connected to the A-lines.

What happens when you brake a paraglider so much that the air speed falls below the minimum speed of about 25km/h?
The photo shows what happens when you pull so much brake that the air speed of the paraglider falls below its minimum speed. The glider stalls. Therefore we sometimes call the minimum speed of a paraglider the stall speed.
Don't do this while flying! Unless you are on an SIV- or acrocourse.
Older gliders can also enter a deep stall when you brake too much - see the chapter on Aerodynamics.

Which pre-launch check is the most important?
Even though all newer harnesses have a safety feature to prevent you from falling out of the harness if you forget your leg straps, this is very uncomfortable and on an older harness it may be a fatal mistake. Checking lines and canopy is of course very important as well.
See the section on Launching in the Basic techniques chapter.

What is the weight of the fabric used to make paraglider canopies? (g/m2)?
Very light fabric strong enough for paragliders can be as light as 25g/m2. Very strong and heavy fabric weighs 40g/m2 or more.
At around 35g/m2, you can calculate that the weight of the fabric of just the top and bottom sail of a 25m2 canopy is a bit less than two kilos.

How tight do you need to pull the leg straps of the harness?
The tightness of the leg straps does not influence the flying properties of the paraglider.
When the leg straps are too loose, after take-off you will find yourself hanging low under the seat and it's more difficult to get in the harness.
Too tight will hinder your movements during take-off, depending on the harness design. In some harnesses it will prevent you from getting into the seat fully.

You're on a straight course and you don't need to change direction any time soon. What do you do with the brake handles?
Modern paragliders fly best without any brake applied - at the so-called trim speed.
But by applying a little bit of pressure, you take out the slack in the brake lines. You feel better what the wing is doing and you can react quickly and subtly to keep the wing straight overhead. This is called active flying.
If you have some more experience it doesn't hurt to let go of the brake handles and relax, but only if it's safe to do so.
You just landed. What do you do?
Directly after landing, look around for other gliders that are about to land and clear the landing area as quickly as possible, without disturbing others.

Despite a good flare, you have a lot of speed just before touching down, because you landed with the wind in your back. What do you do?
A is the safest option if you're not familiar with a PLF (parachute landing fall) which needs practise. Your legs are much stronger than your back or arms.
Although on a flat grassy surface, you could get away with answer B, it can be very dangerous when stones, holes or other objects are hidden in the grass.
Using the protection in your harness as a landing option is not safe - would you park your car against a wall at full speed because the airbags will catch the blow?
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