The grading distribution of a course is given as follows:
Course Components / Weightings
Test 1 - 25%
Test 2 - 25%
Exam - 50%
A final grade of at least 70% is required to pass this course. Suppose that you received a mark of 60% in Test 1 and you just finished Test 2. If x (as a decimal between 0 and 1) represents the mark you will get in Test 2, find the minimum mark y (as a decimal between 0 and 1) you need to get in the exam as a function of x in order to pass the course. What is the domain of this function?