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Find the missing dimension. Use the scale factor 1 : 12.
Item Model Actual
Football helmet Diameter: mm Diameter: 21 cm

Although changes result from business transactions, the equality of the fundamental bookkeeping equation must remain. t/f

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).