Ahot air balloon rising vertically is tracked by an observer located 7 km7 km from the lift‑off point. at a certain moment, the angle between the observer's line of sight and the horizontal is ,π5, and it is changing at a rate of 0.2 rad/min.0.2 rad/min. how fast is the balloon rising at this moment? let yy be the height of the balloon (in km), be time (in minutes), and thetaθ the angle between the line‑of‑sight and the horizontal (in radians). (use decimal notation. give your answer to two decimal places.)

An incident ray through the focal point of a spherical mirror will: reflect through the center of curvature. reflect back through the focal point. reflect parallel to the principle axis. reflect the same direction as the incident ray.

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

Which of the following statement is false