Answer:
d. They are often keystone species
Explanation:
Top predators in an environment are the largest predators and sits on the top (apex) of the food chain in an ecosystem which do not have any natural predators.
As the top predators relative to its abundance has disproportionately large effect on its natural environment, they are the keystone species most of the time.
Hence option d. They are often keystone species is the right option.
Explanation:
The planet Mars has two moons. Phobos and Delmos (i) phobos has period `7` hours, `39` minutes and an orbital radius of `9.4 xx 10^(3) km`. Calculate the mass of Mars. (ii) Assume that Earth and mars move in a circular orbit around the sun, with the martian orbit being `1.52` times the orbital radius of the Earth. What is the length of the martian year in days? `(G = 6.67 xx 10^(-11) Nm^(2) kg^(-2))`
Answer:
plz tell which is your following