Hi,
I can’t really answer the first question, but you should use a ruler to measure the length of the route and of the segment in blue and white in the lower right and then write a proportion. If you need help with that just let me know. The answer to the second question is summer monsoon, because as you can see the red arrows point to India from Africa, while the blue ones go the opposite direction.
Hope this helps! If I was not clear enough or you’d like further explanation please let me know. Also, English is not my first language, so I’m sorry for any mistake.