There is no requirement in the syllabus to calculate the scale change across a Lambert's Chart. You should however be aware that the chart is at minimum scale at the parallel of origin, maximum at the northerly and southerly edges. With SPs 16 degrees apart the scale variation from the nominal (SP) scale is about 1%, so the answer should be about 2% larger, or 1:1,960,000. The last bit is not relevant to the course.
Second one we need a wind to calculate accurately. Still-air the time for 360 nm at 457 kts would be about 47 minutes, so 50 minutes with the delay. 360 nm in 50 minutes is 430 kts TAS. Try that (do not have my CRP-5 here.
I'll be back - have to go teach.
Send Clowns
BCFT