The first commercially licensed radio station in the united states is

angle a = 40.6°

step-by-step explanation:

for any right angle triangle we know the pythagoras theorem reveals

hypotenuse² = height²+base²

by this formula we will calculate the length of hypotenuse

h² = 6²+7²

⇒ h =√36+49 = √85 = 9.22

now from the given triangle sin a = height/ hypotenuse

                                                sin a = 6/9.22 = 0.651

therefore

so angle a = 40.6°

the correct answer is "c: merchants" and "e. soldiers".

the song dynasty was known as the first government in the world to introduce paper currency. it was also the first chinese government which established a permanent standing navy. finally, the first compass was introduced during this period of government.

all of these innovations heavily affected commerce in a positive way. printed money dynamize commerce within the borders of the empire due to an easier way to quantify value during the trade. the introduction of the compass trade routes to be faster. finally, the introduction of a standing navy regulate trade routes.

regarding military affairs, gunpowder was created during this period. this was a tremendous improvement that was widely utilized by the military in order to innovate in the manufacturing of weapons.