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Katarina [22]
3 years ago
8

A geologist is studying rock layers in an old river bed, and he finds a fossil of a fish and a horsetail rush in the same rock l

ayer. According to the law of faunal and floral succession, the geologist can assume that the rock containing the fossils may date back as far as the _____.
Cambrian period
Ordovician period
Silurian period
Devonian period

Physics
2 answers:
erastovalidia [21]3 years ago
8 0

The correct answer is Devonian period.

This is known to be the period of fishes which occurred 416 million years ago. It is known to be the fourth period of the Paleozoic Era. Significant events like evolution of first insects and other animals.

The Fishes evolved in the Ordovician era but the horses were found in the Devonian period only.

KonstantinChe [14]3 years ago
6 0
A geologist is studying rock layers in an old river bed, and he finds a fossil of a fish and a horsetail rush in the same rock layer. According to the law of faunal and floral succession, the geologist can assume that the rock containing the fossils may date back as far as the <span>Devonian period</span>.
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Answer:

Standard deviation = 3

Explanation:

Given

N = 1201

SS = 10800

Required

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First, we need to determine the variance;

Variance = \frac{SS}{N - 1}

This gives:

Variance = \frac{10800}{1201 - 1}

Variance = \frac{10800}{1200}

Variance = 9

Know that:

Variance = SD^2

Where SD represents standard deviation

This gives

9 = SD^2

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SD = \sqrt 9

SD = 3

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Which of the following examples does not make use of total internal reflection?
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Why do astronomers use the word on to describe angles on the sky rather than angles in the sky?
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What best describes the motion of the medium particles in a longitudinal wave? The medium does not move. The medium moves in all
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<h3>What is a longitudinal wave?</h3>

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It requires some medium to travel. A mechanical and sound wave is an example of a longitudinal wave.

Hence in the motion of the medium particles in a longitudinal wave, the medium vibrates parallel to the direction of the wave.

To learn more about the longitudinal wave refer to the link;

brainly.com/question/8497711

3 0
2 years ago
A toy cannon launches a 46-g golf ball straight up into the air with a kinetic energy of 6.8 J. What must the
Shkiper50 [21]

Answer : The correct option is, (C) 17 m/s

Explanation :

Formula used :

K.E=\frac{1}{2}mv^2

where,

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v = velocity

Now put all the given values in the above formula, we get:

K.E=\frac{1}{2}mv^2

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6.8kg.m^2/s^2=\frac{1}{2}\times 0.046kg\times v^2

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Therefore, the ball's velocity be as it leaves the cannon is, 17 m/s

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