What borders mexico on all four of its sides?

Computer models can scientists predict weather. some computer models can show the predicted path of hurricanes. what other events could a computer model warn us of? a) undersea earthquakes , tornadoes, and avalanches b) tornadoes c) avalanches d) undersea earthquakes

Given: circle a externally tangent to circle b. how many possible common tangents to circles a and b can exist? 2 3 4

How would you find the measure of one interior angle