When did Texas and Mexico sign a piece treaty?

they signed the peace of treaty February 2, 1848

The Treaty of Guadalupe Hidalgo, signed on February 2, 1848, ended the Mexican War, recognized the annexation of Texas to the United States (consummated nearly three years before), and ceded to the United States Upper California (the modern state of California) and nearly all of the present American Southwest between California and Texas.

Explanation:

the three roles stated in the dialogue develop the siblings' personalities.

lloyd's personality looks like a trademarketer

dana's personality is afraid from lloyd's behavior and the oldest sister is a decided person who tries to solve any conflict

a. poison gas was sprayed over battlefields by airplanes to weaken enemy positions before major attacks.