Which answer is a scientifically accurate description of velocity?

the hiker began hiking the park's five-mile north hiking trail at 8: 00 a. m. with plenty of daylight left to complete the hike before dark.

the motorcyclist traveled along a highway at 55 mph and reached the campsite in less than the two-hour estimated time.

walking south along the two-mile canyon trail generally takes less time than traveling the same trail north because walking south is all downhill.

the boat traveled from the dock north to the 200-meter marker in the bay in less than 5 minutes, giving the passengers several more hours to fish.

While studying chemical reactions and conservation of matter, sarah's class conducted a variety of experiments. sarah and her lab partner found the mass of a wax candle and placed the candle in a flask. the students lit the candle and let it burn to completion. all that was left was wax and charred candle wick. per their teacher's instructions, the students found the mass of the products. their data can be seen in the data table. formulate a hypothesis the students could test to explain why the experiment did not support the law of conservation of matter. a) the students could repeat the experiment using different candles; there might have been a flaw in the candle. b) the experiment should be repeatable. the students should run several trials and then take an average of the after mass in each trial. c) the students should have someone in the class check their measurement skills as they repeat the experiment. they may have made an error using the balance. d) the students should burn the candle in a container that has some type of lid so that any gas that is a product of the reaction can be contained and massed. submit

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?

What is the measurement of how fast an object moves relative to a reference point?