I need help please
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Trumpeter a holds a b-flat note on the trumpet for a long time. person c is running towards the trumpeter at a constant velocity. person b is running away from the trumpeter at the same rate. person d is standing still the whole time. which person hears a frequency that is lower than the b-flat?

The ballistic pendulum was invented in 1742 by english mathematician benjamin robins. it consists of an initially stationary pendulum that moves after being struck by a bullet, and it is used to measure the original velocity of the bullet. the known variables are the bullet's mass m, the pendulum's mass m, and the height to which the block and bullet swing, determined by the length of the pendulum l and final angle θ. two principles of physics are necessary to solve for the bullet's original velocity. what are these principles? conservation of momentum and newton's third law conservation of energy and conservation of angular momentum grade summary deductions 0% potential 100% conservation of momentum and newton's second law. newton's second law and conservation of angular momentum. conservation of energy and newton's third law conservation of momentum and conservation of angular momentum. conservation of momentum and conservation of energy conservation of energy and newton's second law.

Although light from the sun appears white, it is actually made up of a lot of different colors. this portion of the electromagnetic spectrum, we call white light is referred to as within the electromagnetic spectrum.