Sys《
全国人类学家
提出的要求。
*
高等学社会公布的第一本非茶,​

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

: -)

the answer is c.) there is a warm front in region a and a stationary front in region b.