I think your answer would be (D) microscope with a video camera
Hope i helped!
Answer:
particle's potential energy = 70J
Explanation:
From conservation of energy; K1 + Ue1 = K2 + Ue2
where K1 and K2 are the kinetic energies at two positions and Ue1 and Uue2 are the electrical potential energies at two positions.
k1 = 10J, Ue1 = 100J
K2 = 40J
substitute into K1 + Ue1 = K2 + Ue2
Ue2 = K1 + Ue1 - K2
= 10 +100 - 40
Ue2 = 70J
Answer:

Explanation:
v = Orbital speed = 130 km/s
d = Diameter = 16 ly
r = Radius = 
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²

As the centripetal force balances the gravitational energy we have the following relation

Mass of the the massive object at the center of the Milky Way galaxy is 
Answer:
im pretty sure nuclear if not nitrogen
Explanation:
Answer: y = 40 + 21t
Explanation:
Apply the equation of distance covered.
d = vt + C
Where d is the distance covered
v = velocity , t = time
C = constant = initial distance covered
For the case above....
d = y
y(t) = vt + C
But y(0) =40 = C
C = 40ft
velocity v = 21 ft/s
Therefore, the equation of the altitude is given by;
y(t) = 21t +40
y = 40 + 21t