Question

answer this question and also explain it ​

Answer 1

Answer:

Let the total distance it travelled be 2x.

Time taken to travel first half = x/v1

Time taken to travel second half = x/v2

Therefore, average speed = 2x/(x/v1 + x/v2)

= 2(1/v1 + 1/v2) = 2×v1×v2/(v1+v2)

Answer 2

please refer to the attachment