Answer:
D. Strong nuclear forces hold the nucleus of an atom together. Weak nuclear forces are involved when certain types of atoms break down.
Explanation:
the answer i think is asphalt and plastic
Answer:
E. downward and constant
Explanation:
Freefall is a special case of motion with constant acceleration because the acceleration due to gravity is always constant and downward. This is true even when an object is thrown upward or has zero velocity.
For example, when a ball is thrown up in the air, the ball's velocity is initially upward. Since gravity pulls the object toward the earth with a constant acceleration ggg, the magnitude of velocity decreases as the ball approaches maximum height. At the highest point in its trajectory, the ball has zero velocity, and the magnitude of velocity increases again as the ball falls back toward the earth.
Answer:
a.
b.
c. 
Explanation:
Use Gravitational Force:

Use values given to have the results.
b.

Use m as the mass of the Moon. Using values of a. and m you have the answer.
c.

Use M mass of the planet. Use value of a and Mass of Planet.
Answer:
D. is greater for turbulent flow than for laminar flow
Explanation:
what is friction drag?
- friction drag is a phenomenon experienced when a body moves through a fluid. A practical example can be seen in the mild warmth we experience rubbing the palm's of one's hand together only in this case we are dealing with a solid body and a fluid (e.g air, water). friction drag is directly proportional to the area of the surface in contact with the fluid and increases as velocity increases. We see a practical example of this when the rate at which one rubs the palms together is fast but we use the word turbulent when we are dealing with fluids. Turbulent flow creates more friction drag than laminar flow( Flow between a smooth body and fluid) due to its greater interaction with the surface of the body
- it is important to know that friction is also called viscous drag or skin drag
- I recommend Richardson and coulson vol 2 textbook, page 149, Chemical enginering fluid mechanics textbook by Ron dardy, page 341 for clearer explanation