Pls help me Idk how to do this

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¯¯¯¯¯¯¯¯)?

Suppose you just purchased a digital music player and have put 8 tracks on it. after listening to them you decide that you like 4 of the songs. with the random feature on your player, each of the 8 songs is played once in random order. find the probability that among the first two songs played (a) you like both of them. would this be unusual? (b) you like neither of them. (c) you like exactly one of them. (d) redo () if a song can be replayed before all 8 songs are played.

The correlation coefficient between the number of students and marks obtained in end semester exam. (13 marks) give the statistical meaning of the relationship between the number of students and marks b. obtained in end semester exam. (3 marks) draw the number of students and marks obtained in end semester exam scatter diagram c. (4 marks) check list write your name and id corectly write the question number properly use your own calculator. show all the steps to solve the problems. use the correct formula. answer in provided time. don't use your mobile for any purpose. write your answer up to two decimal places