What you need to know is that the force is
F=ma
The force is the product of mass and acceleration
this means that the acceleration is
a=F/m
a) The force is halved?
this means that f will be

now:
a=

So the accelaration will also he halved (it's the original acceleratation divided by 2)
b) The object's mass is halved?
a=

=a=

which is the original acceleration times two!! so it will double
c) The force and the object's mass are both halved?
now we have
a=

=a=

=a=

so they will cancel each other out and the acceleration will stay the same!
Heat comes from the movement of molecules so it's B
Not sure.can you give me a clue?
Answer:
205N
Explanation:
The net force (F) is the difference between the applied force(
) and the kinetic frictional force(
). i.e
F =
-
-----------------(i)
Note that;
= μmg
Where;
μ = coefficient of kinetic friction
m = mass of the body
g = acceleration due to gravity = 10m/s²
Equation (i) then becomes;
F =
- μmg -------------------(ii)
<em>Given from question;</em>
m = mass of motorcycle = 150kg
μ = 0.03
= 250N
Substitute these values into equation (ii) as follows;
F = 250 - (0.03 x 150 x 10)
F = 250 - (45)
F = 205N
Therefore, the net force applied to the motorcycle is 205N