In Sam's pet corner, there are puppies and parrots. They have a total of 15 heads and 50 feet. How many parrots and how many puppies are there? (Yeah, I know-it's a weird question. I mean heads and feet. Is it even safe?
I'm kidding...sorta.)
Whoever helps me out with this problem, thanks a lot!

Acompany manufactures large valves, packed in boxes. a shipment consists of 1500 valves packed in 75 boxes. each box has the outer dimensions 1.2 x 0.8 x 1.6 m and the inner dimensions 1.19 x 0.79 x 1.59 m. the boxes are loaded on a vehicle (truck + trailer). the available capacity in the vehicle combination is 140 m3. each valve has a volume of 0.06 m3. - calculate the load factor on the box level (%). - calculate the load factor on the vehicle level (%). - calculate the overall load factor (%).