$a)$

$k\approx 1400$

$l\approx 78900$

$m\approx 23900$

$n\approx 108000$

$o\approx 348000$

 

$b)$

$k\approx 1000$

$l\approx 79000$

$m\approx 24000$

$n\approx 108000$

$o\approx 348000$