If you built a a sidewalk around a lion's den and it had a radius of 11 m on the outer edge of the sidewalk and a radius of 9 m and the inner edge of the sidewalk . write and simplify the expression for the exact area of the sidewalk, and find the approximate area of the sidewalk using 3.14 to approximate pi.

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 (%).