Air column: space within the percussion instrument that determines the pitch. Percussion: sounds produced by striking the instrument with a mallet or stick, or striking one instrument against another. 2. Review the process of forming a hypothesis and making a prediction.
Dig short, shallow rows. The rows should be no more than 1/2 inch (1.5 centimeters) deep and spaced 4 inches (10 centimeters) to 6 inches (15 centimeters) apart. 3. Drop the seeds into the rows. Space the seeds approximately 1 inch (25 millimeters) apart in order to allow the onions enough room to grow and mature.
Plant the onions in the soil differently, depending if you are using seeds, seedlings or sets. 1  If you are growing sweet onions from seeds, plant each seed 3/8 of an inch (1 cm) deep and 1/2 inch (1.3 cm) apart.2  When you plant rows, make sure they are 15 inches (38 cm) apart. Rows should remain separated by 15 inches (38 cm). 2  If you are planting sweet onions from sets, plant them 3 inches (7.6 cm) apart, and rows at 15 inches (38 cm) apart. 3  Plant them shallowly, with the roots into the ground, and the bulb only about 1/4 inch (0.6 cm) into the ground.