Need answers to these please.
1. Longitudinal separation minima based on time for aircraft at the same cruising level when navigation aids permit frequent determination of position and speed will be :
(a) 15 minutes
(b) 10 minutes
© 5 minutes
2. A test call shall not continue for more than :
(a) 8 seconds
(b) 12 seconds
© 10 seconds
3. When may the crew use the SELCAL facility of an HF set?
(a) When ATC publish facility is available
(b) When the crew specifically obtain ATCs permission to use it
© Both (a) & (b)
(d) Neither (a) nor (b)