PLS help my grade is depending on also just telling me how to do it will help

Arley is building a model of a city map. in one part of the city, three roads form a right triangle, which harley draws as triangle abc, with the following measures: m∠b=90° and m∠a=30°. in his scale model, the hypotenuse of triangle abc, ac¯¯¯¯¯¯¯¯, has a length of 817−−√ cm. what is the value of a (the length of bc¯¯¯¯¯¯¯¯)?

Somone me i want to know what 18 hours out of 24 hours in a fraction

Teams of 4 are competing in a 1/4 mile relay race. each runner must run the same exact distance. what is the distance each teammate runs?