Its given that, (Let consider the index of Queue is starting from 0).
data[0] to data[6] are empty.
data[7] to data[15] are filled with the elements.
Capacity is 19. Hence data[16] to data[18] are still empty.
We can easily see that
Front is poiting to the location = 7
Rear is pointing to the location = 15.
Hence If you enter new element then it will get inserted at Rear pointer.
Since Rear < Capacity-1, Hence insertion will be successful.
Hence New element will get inserted at location 16.