A reference frame attached to the earth (a) is an inertial frame by definition
Answers
A reference frame attached to the earth - a) is an inertial frame because Newton's laws of motion are applicable in this frame. b) is an inertial frame by definition. c) cannot be an inertial frame because earth is revolving around sun.
Answer: Earth cannot be an inertial frame of reference because the Earth is rotating about its own axis as well as revolve around the sun.
Explanation: Accelerating frame of reference is always non inertial frame.
But we may think that any frame in which Newton's laws are applicable is an inertial frame and on Earth an object obeys these laws but it does not it's only us who see the objects obeying the laws because we are also on Earth and any person outside the Earth will not see the objects on Earth obeying the Newtonian laws.
I hope u all understand.