The appropriate interrogative word for the sentence is Cuántas , making the complete question "¿Cuántas horas estudias cada noche?" This word asks about the quantity of hours being studied. Understanding how to use such interrogatives is key to forming accurate questions in Spanish. ;
Approximately 2.81 x 10^21 electrons flow through an electric device delivering a current of 15.0 A for 30 seconds. This is calculated by first determining the total charge using the current and time, then converting that charge to the number of electrons. Each electron has a charge of about 1.6 x 10^-19 Coulombs.
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