Answer:
a) The net force acting on the sleigh is zero because it is moving at a constant speed.
b) 
, then 
.
Gravitational field exists in
the space surrounding a charged particle and exerts a force on other charged
particles. Gravitational waves are ripples of waves travelling outward from the
source. The more massive the orbit of two bodies, the more it emits
gravitational wave. And everything around it that is near within the wave
experiences a ‘pull’ toward the orbiting bodies.
You get the net force acting on it ... the sum of the strengths and directions
of all the individual forces there may be.
Theres: the vacuole, nucleus, rough endoplamid reticulum, smooth endoplasmic reticulum, cell memebrane, cell wall, chloroplast, mitochondria, golgi apperatus, lysosomes, and ribosomes
