1)
Did the nation blow both Teki'ah and Teru'ah?
1.
Malbim: No. The Kohanim blew a long Teki'ah and the nation blew Teru'ah. The nation blew Teru'ah immediately after hearing the long Teki'ah; the sounds mixed together.
2)
Did Rachav's house fall when the wall of the city fell?
1.
Malbim (2:15): It did not, for her house was outside the wall; three of its walls were the city wall, and the window was in the fourth direction. She dwelled in [an area surrounded on three sides via] the wall [and the wall fell towards the city].