Before going to answer this question, first we have to understand centripetal force.
The centripetal force is the force which is required to keep the body along its circular path.The direction of the force is along the radius and towards the centre.

Here m is the mass of the body,v is the velocity of the body and r is the radius of the circular path.
When a body moves in a circular path,its velocity at any point is the tangent drawn at that point.
As centripetal force acts along the radius, it must be perpendicular to the velocity of the body.
Hence the correct answer to the question is- It acts perpendicular to the velocity and is directed toward the center of the circle.
Answer:
Alcohol and drugs are a no no. you should put the answers in so people can answer correctly.
The frequency of any repeating event is the number of times it happens in some specified period of time.
The frequency of a wave is the number of cycles, wiggles, compressions etc. that occur in a given time, usually one second.
A: Human Body
C is wrong because they don’t have the tools to test it on another planet
Before we start thinking about the snowball, we need to remind
each other that energy is "conserved". That means that if you
ever see energy decrease in one place, then the missing amount
must have gone somewhere, and if you ever see energy increase
in one place, then the energy that appeared must have come from
somewhere. Energy does not magically appear or disappear.
So you toss a snowball out of your hand. As you let it go, you give
it some kinetic energy, and it starts rolling along the ground.
Once you let go of it, it can't get any more energy (unless it has
some kind of little tiny engine inside it).
Kinetic Energy = (1/2) (mass) (speed)² .
and that amount can't change.
So if extra snow sticks to it as it merrily rolls along, and its mass
increases, then it must slow down.