Answer:
When you are running the most important force that you should understand is friction. Friction is a force that opposes movement between two objects, but for runners friction makes you faster. Friction gives you a better and more efficient way to use your energy into speed.
Here I come and we wanna go home!!!
Answer:
Heyyy hope this helps
Convection currents describe the rising, spread, and sinking of gas, liquid, or molten material caused by the application of heat.
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!