Which of the following explains why more aluminum drink cans are recycled than plastic bottles? A. Aluminum is better for closed-loop recycling.
B. Plastics can only be down-cycled.
C. Aluminum is more energy efficient to recycle.
D. Plastics are not included in single-stream recycling.
(THE SUBJECT IS "SCIENCE AND MATHEMATICS IN THE REAL WORLD") I cannot find an answer anywhere else.

At 12 noon, the count in a bacteria culture was 400; at 4: 00 pm the count was 1200 let p(t) denote the bacteria cou population growth law. find: (a) an expression for the bacteria count at any time t (b) the bacteria count at 10 am. (c) the time required for the bacteria count to reach 1800.

Manometers are good examples of measuring instruments, nowadays they are not as common as before. a)-capacitive probe gauges b)-gravitational gauges deformation ) gauges d)-digital gauges

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]