Answer:
Acceleration = 9.8 m/sec2
Explanation:
We know that the acceleration due to gravity is 9.8 m/sec2 near the surface of earth.
Remember that the gravity is always affecting everything on earth at every instant, even the rock at the very top of it's trajectory. It doesn't mind if the velocity is zero for an instant or if there's air resistance, the gravity force is there, and always aims towards the center of the earth.
So for all the trajectory of the rock, gravity is 9.8 m/sec2
Answer:
Magnetic field, B = 
Explanation:
It is given that,
The amplitude of an electromagnetic wave, E = 470 V/m
We need to find the amplitude of the corresponding magnetic field. The relation between electric and magnetic field is :

Where
c is the speed of light

B = 0.00000156

So, the amplitude of the corresponding magnetic field is
. Hence, this is the required solution.