Answer:
Science is supported by facts and processes.
Science involves observation and experimentation.
Science continually changes and is constantly updated.
weight is vector vary from place to place
Answer:

Explanation:
consider the mass of each train car be m
m₁ = m₂ = m₃ = m
speed of the three identical train
u₁ = u₂ = u₃ = 1.8 m/s
m₄ = m u₄ = 4.5 m/s
m₅ = m u₅ = 0 (initial velocity )
final velocity
v₁ = v₂ = v₃ = v₄ = v₅ = v
using conservation of momentum
m₁u₁ + m₂u₂ + m₃u₃ + m₄u₄ + m₅u₅ = m₁v₁ + m₂v₂ + m₃v₃ + m₄v₄ + m₅v₅
m (1.8 + 1.8 + 1.8 +4.5) = 5 m v


Yes because mercury has more protons and electrons that tin. (30 more)
Use the following formula for the electric field strength between two parallel plates:
E = V/d
where,
V: potential difference = 25V
d: distance between plates = 5 cm = 0.05 m
Replace the previous values of the parameters into the formula for E:

Hence, the electric field strength is 500V/m