$19)$ Consider two programs implementing algorithms A and B$,$ trying to solve the same problem for an input of size n$.$ They measured the execution times for test cases of different sizes and tabulated them as follows. Which program is more efficient? Why?

Algorithm n $=100$ n $=200$ n $=300$ n $=400$ n $=500$

A $0\mathrm{.}003$s $0\mathrm{.}36$s $0\mathrm{.}36$s $0\mathrm{.}24$s $0\mathrm{.}053$s

B $0\mathrm{.}040$s $0\mathrm{.}160$s $0\mathrm{.}360$s $0\mathrm{.}640$s $1\mathrm{.}000$s