Index fossils are used to determine the relative ages of rock and fossils and are also used to define the boundaries between geologic periods.
<u>Option: A</u>
<u>Explanation:</u>
The fossils which are recognized as fossils guides or indicator fossils are used to classify and recognize geological or faunal periods, termed as index fossils. It must be of short vertical reach, wide geographic distribution and swift patterns in evolution. It helps to assess the rock layers ' age and helps to date other fossils found close and around them. For an instance, Ammonites were abundant in the Mesozoic period between 245 to 65 mya, they have not been found after the Cretaceous era, as they became endangered during the K-T extinction (65 mya).
Answer:
Explanation:
Distance and direction of an object's change in position from a starting point. Displacement. 3. Jermaine runs exactly 2 laps around a 400 meter track. What is the displacement? 0 ... David walks 3 km north, and then turns east and walks 4 km. ... A person walks 50 meters directly north, stops, and then travels 32 meters
Answer:
True
Explanation:
Velocity is a vector quantity, which means that it carries both magnitude and direction. Hence when direction of a particle changes, although magnitude (speed) may remain same, it's velocity changes due to direction change. For ex. A particle is m... A particle is moving along x axis with speed 1m/s, it's velocity will be represented as 1i (i represents unit vector along x)
But if it now starts moving along y axis, it's velocity is 1j (j represents unit vector along y axis). Hence velocity changes with direction.
brainllest pls .
According to the Bernoulli's equation,the pressure difference between the wide and narrow ends of the pipe is given by
Here, is the velocity of water through wide ends of cylindrical pipe and is the velocity of water through narrow ends of cylindrical pipe.
Given,
Now from equation continuity,
.
Here, and are cross- sectional areas of wide and narrow ends of cylindrical pipe.
As pipe is circular, so
.
At the second point, the diameter is halved, which means the radius is also halved. Therefore,
Substituting these values with the density of water is in pressure difference formula we get.
Answer:
The change in temperature,
Explanation:
Given that,
The temperature in Spearfish, South Dakota, rose from in just 2 minutes. We need to find the temperature change in Celsius degrees. Change in temperature is given by final temperature minus initial temperature such that,
The relation between degrees Celsius and degrees Fahrenheit is given by :
Here, F = 49 degrees
So, the change in temperature is 9.45 degree Celsius. Hence, this is the required solution.