Solve the picture pls

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¯¯¯¯¯¯¯¯)?

Which equation expression the relationship between the number of boxes b and the number of cans c and the proportion is 48

    choose the correct definition for  extremo.  a.  end      b.  extra      c.  extract      d.  eventual