I need some help I suck at math‍♂️‍♂️

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¯¯¯¯¯¯¯¯)?

25 ! the line of best fit is h = 5a + 86. predict the height at age 16. show your work.

An ulcer medication has 300 milligrams in 2 tablets. how many milligrams are in 3 tablets?