21947÷205 divide and check the result

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¯¯¯¯¯¯¯¯)?

The measurement of one angle of a right triangle is 42° what is the measurement of the third angle? (there is no picture)

How many square centimeters of wrapping paper will be used to wrap the shoe box?