Answer:
56
Explanation:
I just want the points to be completely honest with you.
Answer:
a. Light pollution refers to light used for human activities that brightens the sky and hinders astronomical observations.
Explanation:
Light pollution is due to the excessive and misdirected use of artificial light. Light bulbs are often design in an incorrect way, since a great part of its light is not completely directed to the ground and an important percentage is emitted to the sky in where will be scattered and reflected back to ground by the particles in the atmosphere. That brings as an effect a sky glow, therefore the visibility of astronomical objects will be extremely reduce.
Hence, professional astronomical research and amateur observations will be affected. Light pollution has a negative impact on bird migration at night and in the health of difference species, humans also.
Answer:
320 N/m
Explanation:
From Hooke's law, we deduce that
F=kx where F is applied force, k is spring constant and x is extension or compression of spring
Making k the subject of formula then

Conversion
1m equals to 100cm
Xm equals 25 cm
25/100=0.25 m
Substituting 80 N for F and 0.25m for x then

Therefore, the spring constant is equal to 320 N/m
Answer:
C) 40,000 Joules
Explanation:
½(1000)10² - 10000 = 40000
Step 1: list known info
distance(change in position (Δx))= 18m+22m= 40m
time= 20 seconds
Step 2 :solve for velocity
velocity= Δx÷time
v= 40/20= 2m/s
Answer: the velocity is 2 meters per a second (m/s)