50 POINTS !!
PLEASE HELP !! ILL GIVE BRAINLIEST TO THE RIGHT ANSWERS.

Step-by-step explanation:
simple this is a right angle triangle, 90⁰, the red box inside the triangle indicates 90⁰
cos 90=7.4/c
c cos 90 = 7.4
c= 7.4/cos 90
c = 0