What is the t- critical value for the confidence levek of c=92 and 19 degrees of freedom

If the graphs of the linear equations in a system are parallel, what does that mean about the possible solution(s) of the system? a. there are infinitely many solutions. b. there is no solution. c. there is exactly one solution. d. the lines in a system cannot be parallel.

In the 30-60-90 triangle below side s has a length of and side r has a length

How do you write something in scientific notation?