Answer: True
Explanation:
The index fossil are the fossils that are of animals and plants that remained preserved in the rock of the earth. It describes the particular span of the geological time or the environment. An index fossil can be easily recognized, is widely distributed and abundant.
The index fossil is the basis for defining the boundaries of the geological time scale with the correlation of the strata.
Those organisms which exhibited the short vertical range that is the life span on earth and the wide lateral range that is geographic distribution can be included as index fossil.
These fossils are indicative of the environment in which the organism used to live.
D) Mars & Jupiter is correct
Answer:
Two stars (a and b) can have the same luminosity, but different surface area and temperature if the following condition is met:
(T_a^4)(R_a^2) = (T_b^4)(R_b^2)
Explanation:
The luminosity of a star is the total energy that produces in one second. It depends on the size of the star and its surface temperature.
L = σ(T^4)(4πR^2)
L is the luminosity f the star, T is the temperature of the surface of the star and R is its radius.
Two stars can have the same luminosity if the relation between the radius and the surface temperature is maintained.
To see this lets suposed you have 2 stars, a and b, and the luminosities of each one of them:
L_a = σ(T_a^4)(4πR_a^2)
L_b = σ(T_b^4)(4πR_b^2)
you can assume that L_a and L_b are equal:
σ(T_a^4)(4πR_a^2) = σ(T_b^4)(4πR_b^2)
Now, you can cancel the constants:
(T_a^4)(R_a^2) = (T_b^4)(R_b^2)
as long as this relation between a and b is true, then the luminosity can be the same.
Jupiter, umm I just know it
