Darla and Rob plan an investigation to see if adding weights to a car affects its speed down a ramp. Their experimental setup consists of a ramp made of a piece of wood that is 30 cm long. The ramp is propped up on four books to give it a height at one end of 8 cm. What is the independent variable in this investigation?

Answer: 1.4 seconds which is the third optionexplanation: current is defined as the flow of charge per timetherefore, the equation that relates current, charge and time can be expressed as follows: i = δq / δtwhere: i is the current given = 1.8 ampereδq is the charge given = 2.5 coulombδt is the time required for the flow of the given charges to give the 1.8 ampere.substitute with the givens in the above equation to get the time as follows: 1.8 = 2.5 / δtδt = 2.5 / 1.8 = 1.38888 which is approximately 1.4 secondshope this was !

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