calculate or get price of parent items on bill of materials

i want to calculate or get the price of parent items on bill of materials query

here is the fiddle-> https://www.db-fiddle.com/f/o3jLgZxKNLG14mna8QGdVN/6

please note in the second row, betax has qty = 2 and the other parent items could behave the same

qty of the first row, always will be 1

what i need is to get the 'price' and 'subtotal' for every parent