<h3><u>Answer;</u></h3>
The period of the wave is <u><em>4 seconds</em></u>
<h3>
<em><u>Explanation;</u></em></h3>
- <em><u>The period of a wave or periodic time is the time taken for one complete oscillation to occur.</u></em> In this case, one complete oscillation occurs when the wave moves from one crest to the next or a trough to the next. <em><u>This takes 4 seconds. Therefore the period is 4 seconds.</u></em>
- <em><u>Frequency on the other hand is the number of oscillations by a wave in one second. Thus, f = 1/T, that is frequency is the reciprocal of periodic time.</u></em>
Answer:
C. Dark Matter
Explanation:
Dark matter is estimated to make up 90 percent of the mass of the galaxy.
The dark matter (as astronomers have come to call the invisible material) extends to a distance of at least 200,000 light-years from the center of the Galaxy.
A boiling pot of water (the water travels in a current throughout the pot), a hot air balloon (hot air rises, making the balloon rise) , and cup of a steaming, hot liquid (hot air rises, creating steam) are all situations where convection occurs.
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C is the correct answer, hope it helps
Since the net electric flux which is − 6.89 × 10^6 V⋅m through the hull of the submarine is negative, the number of electric field lines leaving the submarine is less than the number entering it.
A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. Most large submarines consist of a cylindrical body with hemispherical (or conical) ends and a vertical structure, usually located amidships, that houses communications and sensing devices as well as periscopes. In modern submarines, this structure is the "sail".
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