A student builds a model of the heart and lungs, shown in the diagram. Two trucks, 1 and 2, travel between the organs. The student will label the trucks with what they are carrying.
Which set of labels BEST completes the model?

Amount of liquid measured in l or lm

Mike and mitchell decide to have a foot race. they mark off a stretch of 100 yards, and recruit cindy to work the stopwatch. after running the race and looking at the results, cindy declared that mitchell was the fastest. so how did the boys times compare?

Write a balanced equation showing the formation of copper (ii) nitrite from its elements