(a) -267 N
Explanation: if the refrigerator is not moving, it means that the net force acting on it is zero.
We are only interested in the motion along the horizontal direction; there are two forces acting in this direction:
- The pushing force, forward, F=+267 N
- The static frictional force, backward, 
Since the net force must be zero, we have

(b) 363.1 N
The largest pushing force that can be applied to the refrigeratore before it begins to move is equal to the magnitude of the maximum static frictional force, which is given by:

where
is the coefficient of static friction
m = 57 kg is the mass of the refrigerator
g = 9.8 m/s^2 is the gravitational acceleration
Substituting,

Answer:
Explanation:
Given two objects are dropped simultaneously
Object A is 10 m higher than object B therefore
Distance covered by object A is given by
is given by

where y=displacement
u=initial velocity
a=acceleration
t=time

for object B

Subtract 1 and 2 we get

i.e. they will travel equal distance in equal time and distance between them remain 10 m until object B hits the ground
C I completed the same quiz
Answer: 1/R = 1/R1 + 1/R2+ ...+ 1/Rn
R is resistance of system in which there are resistors R1, R2 , ... Rn parallel.
Answer:
you need at least two out of the three to get any aenser