The volume of rain that fells in the field is simply given by the area of the field, which is

multiplied by the height of rain that fell, which is

Therefore, the volume is

A pH scale goes from 0 - 14.
7 is in the middle so it is neutral
2.1) (i) W = mg downwards
(ii) N = R = Normal Reaction from the ground upwards
(iii) Fe = Force of engine towards the right
(iv) f = friction towards the left
(v) ma = Constant acceleration towards right.
2.2.1)
v = 25 m/s
u = 0 m/s
∆v = v - u = (25 - 0) m/s = 25 m/s
x = X
∆t = 50 s

a = 0.5 m/s².
2.2.2)
F = ma = 900 kg × 0.5 m/s² = 450 N.
2.2.3)


2.3)
Fe = f + ma
Fe - f = ma
For velocity to be constant,
a should be 0, or, a = 0,
Fe = f = 270 N
2.4.1)
v = 0
u = 25 m/s
a = -0.5 m/s²
v = u + at
t = -u/a = -(25)/(-0.5) = 50 s.
2.4.2)
x = -625/(2×(-0.5)) = 625 m.
Before you start working on any motion problem, YOU decide which direction you're going to call 'positive'. Everybody almost always calls UP positive, and the acceleration of gravity points down, so it winds up negative. But you could just as well call DOWN the positive direction. Then, the cannonball is fired with a negative vertical speed, and the acceleration of gravity eventually robs all of its negative speed, and makes it start falling in the positive direction. The whole thing is your choice.
Answer:
electromagnetic wave i think
Explanation: