The first rule of vectors is that the horizontal and vertical components are separate. Disregarding air resistance, the only thing we have to worry about is gravity.
The appropriate suvat to use for the vertical component is v = u +at
I will take a to be -9.81, you may have to change it to be 10 if your qualification likes g to be 10.
v = 30 + (-9.81x2)
v = 30 - 19.62
=10.38m/s
Therefore we know that after 2.0 s the vertical component will be 10.38ms^-1, ie 10m/s as the answers given are all to 2sf.
The horizontal component is completely separate to the vertical component and since there is no air resistance, it will remain constant throughout the projectiles trajectory. Therefore it will remain at 40ms^-1.
Combining this together we get:
(1) vx=40m/s and vy=10m/s
I think b but I’m not completely sure
Answer:
The true course: 
north of east
The ground speed of the plane: 96.68 m/s
Explanation:
Given:
= velocity of wind = 
= velocity of plane in still air = 
Assume:
= resultant velocity of the plane
= direction of the plane with the east
Since the resultant is the vector addition of all the vectors. So, the resultant velocity of the plane will be the vector sum of the wind velocity and the plane velocity in still air.
Let us find the direction of this resultant velocity with respect to east direction:
This means the the true course of the plane is in the direction of north of east.
The ground speed will be the magnitude of the resultant velocity of the plane.
Hence, the ground speed of the plane is 96.68 km/h.
In an extremely simplified explanation,
What happens is that the steam (heat) that is generated by the burning of coal is used to rotate the motor of the steam engine.
Frequency = 1/T
as the 5 is reduced, frequency is increase.
as 1 whole wave travels through a point in a lesser time now
