Four significant is an answer
because if 0 is the extreme right of decimal place it is significant
and if 0 lies between two significant figure than it is significant like 1.020 is 4 sifnificant and 100 is 1 significant figure
Answer:
The kinetic energy is 20,000\ J
Step-by-step explanation:
The kinetic energy of a body is defined as:

Where <em>m</em> is the mass of the roller coaster car
<em>s</em> is the speed and <em>k</em> is the kinetic energy
We know that 

Then the kinetic energy of the roller coaster car is:

Answer:
5/14
Step-by-step explanation:
5/14 is the simplified form.