Someone please please help please ASAP please please ASAP ASAP please please help please please ASAP ASAP please please ASAP please

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¯¯¯¯¯¯¯¯)?

Type the correct answer in each box. use numerals instead of words. if necessary, use / for the fraction bar. consider the given table.

Christina can paint 420 square feet in 105 minutes. which unit rate describes the scenario?