Which of the following is not an example of work being done? question 14 options: superman catches mrs. nicol while falling from a burning building and applies an upward force to fly her back up to the rooftop to safety. a force is applied by a chain to a rollercoaster car to carry it up the hill of the first drop of the nitro ride at six flags great adventure. mrs. coyne is holding her dog, cosmo, 1 m off the ground for 20 minutes.

List four observations that indicate that a chemical reaction may be taking place

(1.6 × 10-19)(5.0 × 106) = c × 10d identify the missing numbers below to show the result of multiplying the numbers.

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.