Questions are in the attachments :D

Triangle abc is reflected over the line y=x triangle abc has points (-6,-,-1) and (-5,-6) what is the c coordinate

Given the following sampling distribution of one mean with a sample size 49, from a normally distributed population, find the population standard deviation, o.79828588912497

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)