When $$a $$certain $$perfect $$gas$,$heated $$at $$constant $$pressure $$from $$

$1$

$8$

C $$to $$

$9$

$8$

C

$,$

$$required $$

$1$

$1$

$3$

$6$

$$kJ

$/$

kg $$and $$when $$heated $$at $$constant $$volume $$within $$the $$same $$range $$of $$temperatures$,$it $$required $$

$8$

$0$

$8$

$$kJ

$/$

kgK

$.$

$$Calculate $$the $$characteristic $$gas $$constant $$of $$the $$perfect $$gas$.$