Answer:
490,400 J
Explanation:
Mass of first car, m = 1000 kg
Mass of second car, M = 1200 kg
velocity of first car, u = 20 m/s east
velocity of second car, U = 22 m/s west
The formula for the kinetic energy is

where, m is the body and v be the velocity of the body.
Total kinetic energy is given by



k = 490,400 J
Thus, the total kinetic energy of the system is 490,400 J.
The answer is Decibels. <span />
Reduce friction because friction just makes things harder
Answer:
the angle is given by
Tan theta = 35/59 = 0.59
so theta = Tan ^-1 ( 0.59 )
theta = 30.54 deg.
B. five electrons
If you want an explanation, here it is.
The atomic number gives the number of protons. Protons which have a positive charge are balanced by an equal number of electrons in a neutral atom. Boron number 5 has five protons and therefore as a neutral atom also has five electrons.