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:
Current in outer circle will be 15.826 A
Explanation:
We have given number of turns in inner coil 
Radius of inner circle 
Current in the inner circle 
Number of turns in outer circle 
Radius of outer circle 
We have to find the current in outer circle so that net magnetic field will zero
For net magnetic field current must be in opposite direction as in inner circle
We know that magnetic field is given due to circular coil is given by

For net magnetic field zero

So 

Answer: T is greater
Explanation:
Since the elevator is moving against gravity more work will be done on the rope
T= m(g+a)

- P is power
- R is resistance

Hence


- Therefore if power is low then resistance will be high.
The first bulb has less power hence it has greater filament resistance.
Answer:
drought, floods, rip currents, tropical cyclones, wildfires
Explanation:
right on edge