What is the number of degrees of freedom that should be used for finding the critical value

Acoffee shop orders at most $3,500 worth of coffee and tea. the shop needs to make a profit of at least $1,900 on the order. the possible combinations of coffee and tea for this order are given by this system of inequalities, where c = pounds of coffee and t = pounds of tea: 6c + 13t ≤ 3,500 3.50c + 4t ≥ 1,900 which graph's shaded region represents the possible combinations of coffee and tea for this order?

Graph the line y=4/3 x+1 . use the line tool and select two points on the line.

How do u write a function for the reflection across the y axis