Can someone help me out please?

Given sin=-4/5 and x is in quadrant 3, what is the value of tan x/2

Ineed on this equation what is the real value of x in the equation [tex]log_2}24 - log_{2} 3 = log_{5}x[/tex] a. 3 b. 21 c. 72 d. 125 e. 243

Which of the following statements is not true about regions? a.) regions have fixed boundaries that are determined by the region's inhabitants.b.) a region can be defined by physical characteristics, such as climate, landform, and vegetation.c.) regions can change over time.d.) a region can be defined by human characteristics, such as language, government, and economic activity.e.) the same location can be considered part of multiple regions.