In 390 kilograms of rye there are 13756.85 ounces, to achieve this take 390 and just multiply by 35.27397.
To convert 120 kilograms into ounces multiply by 35.27397 giving 4232.876 ounces.
You've got 310 kilograms of beetroot but someone only wants to buy that in units of ounces, to change the units multiply by 35.27397. Now you have 10934.93 ounces.
You have 570 kilograms of sugarbeet but you need to know how many ounces that is. To get the answer multiply by 35.27397 which gives you 20106.16 ounces.