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. A submerged stone weighs 254 newtons, but out of the water it weighs 1235 newions. The density of the water is 1000 kilograms per cubic meter. The volume of the stone is most nearly (2) 0.100 m (b) 0.206 m3 (c) 0.254 m3 (d) 1.24 m- 19. A fixed quantity of an ideal gas has an initial pressure, volume, and temperature of P). \\"]- and 71 - respectively. The temperature of the gas is doubled. Which of the following sets of values for the final pressure and volume is possible? (2) P , and 1's (b) P , and VI (c) 2P , and 21, (d) 2P , and V1 20. An observer sees the muzzle flash when a hunter fires a gun. If she hears the sound 4.50 seconds later. how far is it from the hunter to the observer? The speed of sound on that day was 340 meters per second. (2) 75.6 meters (b) 153 meters (c) 1530 meters (d) 3060 meters 21. A 50.0-kilogram mass was set on a spring whose spring constant was 850 newtons per meter. How far is the spring compressed? 50.0 kg (2) 5.88 x 10- - m (b) 0.577 m (c) 0.769 m (d) 1.15 m 22. A 15-volt battery is connected to 2 3.0-ohm resistor. as shown. How much power is used by the resistor? (a) 8.3 W 15 V. $ 3.0 n (b) 15 W (c) 45 W (d) 75 W 23. The speed of a pulse along the string is v. What will be the speed in terms of i, if a string with 9 times the mass per unit length of the original is used? (2) 9 (b) 9:1 (c) 31) m (d) w /