$3$a$)$ Write an algorithm to find the maximum element in an array. Also

Compute the total computing time of the above algorithm.

$3b$ Find the Big$-$Oh for the following $f(n).$

a$.f(n)=60n^4+n^6+n^{5}lo{g}_{2}n$

b$.f(n)=n^4+n^3+1000000n^3+n!$

c$.f(n)=100n^2+2^n+n^4$