2) features of the ocean floor; 3) the concept of sea-floor spreading; and. 4) the nature of the Earth's magnetic field and the fact that it has reversed its polarity many times in the past. The Earth's layers â The Earth is a layered planet consisting of crust, mantle and core (Fig. 1).
Run your sprinklers for 15 minutes. Use a ruler to measure the depth of water in each can. Add all the numbers, and then divide by the number of cans to find the average output. This average number is your sprinkler number. It is the average amount of water your sprinklers apply in 15 minutes.
Fill the bucket with water so that the water level inside the bucket and outside the bucket are the same. Mark the water level on the bucket with a piece of duct tape, sharpie or wax pen. Wait at least 24 hours for evaporation to occur, 2-3 days is best but you can see results with shorter time periods.