Answer:
(c) no different than on a low-pressure day.
Explanation:
The force acting on the ship when it floats in water is the buoyant force. According to the Archimedes' principle: The magnitude of buoyant force acting on the body of the object is equal to the volume displaced by the object.
Thus, Buoyant forces are a volume phenomenon and is determined by the volume of the fluid displaced.
<u>Whether it is a high pressure day or a low pressure day, the level of the floating ship is unaffected because the increased or decreased pressure at the all the points of the water and the ship and there will be no change in the volume of the water displaced by the ship.</u>
The frequency of the pendulum is independent of the mass on the end. (c)
This means that it doesn't matter if you hang a piece of spaghetti or a school bus from the bottom end. If there is no air resistance, and no friction at the top end, and the string has no mass, then the time it takes the pendulum to swing from one side to the other <u><em>only</em></u> depends on the <u><em>length</em></u> of the string.
Answer:
a) 42 m/s, positive direction (to the east), b) 42 m/s, negative direction (to the west).
Explanation:
a) Let consider that Car A is moving at positive direction. Then, the relative velocity of Car A as seen by the driver of Car B is:

42 m/s, positive direction (to the east).
b) The relative velocity of Car B as seen by the drive of Car A is:

42 m/s, negative direction (to the west).