Which statement about relative motion is not true? A. A seated passenger on a plane is motionless relative to the plane.
B. A flight attendant walking down the aisle is in motion relative to the plane/
C. A plane appears motionless to a skydiver who jumps out of it.
D. The plan appears to be moving across the sky relative to a person watching from the ground.

Explanation:

laws of physics which apply when you are at rest on the earth also apply when you are in any reference frame which is moving at a constant velocity with respect to the earth. For example, you can toss and catch a ball in a moving bus if the motion is in a straight line at constant speed.

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"