I'm assuming you might not be on a course, as some of these fundamental and should have been emphasised, and so don't necessarily have access to course notes. If you do, look them up for more detailed answers. Otherwise, do you mind if I ask why you want to know?
2. Convergency is the angle between the meridians through two specified points.
3. Precession is the tendency of a force applied to one point of a spinning gyroscope to move the alignment of the axis in the same way as a force applied to a stationary gyro 90° further round, in the direction of rotation. You'd have to ask an instrument instructor about calculating it!
4. Density altitude is the altitude in ISA conditions with the same density as the air for which density altitude is to be calculated. Formula is
DA=PA+118.8xT
DA = Density altitude
PA = Pressure Altitude
T = Temperature deviation from ISA, +ve if warmer than ISA, -ve if colder
6. I believe it's 2½°
7. Warm - cirrus, altostratus, nimbostratus in that order
Cold - cumulus, altocumulus and (often embeddded) cumulonimbus
9. Pressure altitude is the altitude in ISA conditions with the same pressure as the air for which pressure altitude is to be calculated.
Send Clowns,
Gen Nav & Flt Plng, BCFT