Explain why 13233345364715 is a composite no.

A composite number has more than two factors.  In this case, the number 13233345364715 has more than two factors, so it is composite.  

Step-by-step explanation:

Numbers can be classified as prime or composite.  Prime numbers have only two factors, 1 and the number itself.  For example, 13 is a prime number because only 1 and 13 can be multiplied together to get 13.  However, a composite number has more than two factors.  In the case of the numer 13233345364715, I know that there are more than two factors because the number ends in 5, which means it has a factor of 5.  To confirm, divide 13233345364715/5 = 2646669072943. This large of a number may also have other factors, however, since you now know it has at least four factors, it is composite.  

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.