hertz: A unit for measuring frequency, equal to one cycle per second. If a sound wave has a frequency of 20,000 Hz,
<em>Kinetic Energy</em>
=><em><u>It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity.</u></em>
<em>Potential</em><em> </em><em>Energy</em><em> </em>
<u><em>=</em><em>></em><em>potential energy is the energy held by </em></u><em><u>an</u></em>
<em><u> object because of its position relative to </u></em><em><u>other</u></em>
<em><u> objects, stresses within itself, its </u></em><em><u>electric</u></em>
<em><u> charge, or other factors.</u></em>
<h2>Difference:</h2>
=>Potential energy is a <u>stored</u> energy on the other hand kinetic energy is the energy of an object or a system's particle in <em><u>Motion</u></em>.
Answer
given,
change in enthalpy = 51 kJ/mole
change in activation energy = 109 kJ/mole
when a reaction is catalysed change in enthalpy between the product and the reactant does not change it remain constant.
where as activation energy of the product and the reactant decreases.
example:
ΔH = 51 kJ/mole
E_a= 83 kJ/mole
here activation energy decrease whereas change in enthalpy remains same.
Average speed of the driver is given as

if he moved for total time t = 3.5 hours
so the distance between the tow is given as



so the distance between St. Louis and Chicago is 224 miles