(35 points)Take a stone/ pebble and tie it on a string. Perform an activity to investigate the variation of the time period with the length of the pendulum. Follow these steps to complete investigation

Aim

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procedure

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conclusion

Which is not a source of noise pollution? a)airplanes b)acid rain c)machines d)cars

Animals respond in various ways to stimuli detected through their senses. some of these responses are stimulated by the presence of danger. which of these animal responses is the best example of a response to an immediate threat? a) a rooster crows every morning at the first sign of light. b) as something approaches an octopus, it shoots a cloud of ink. c) from late fall until spring, bears hibernate to preserve energy. reactivate d) a dog is getting hot in the sunlight, so he moves to a shaded area.

Afigure skater is rotating at a rate of 200 revolutions per minute. what is the angular speed, in units of rad/s? 20.9 12000 200 3.33