I need help with this

x = 85

Step-by-step explanation:

To solve, first find the angle of the other missing angle in the left by subtracting the outside angle from 180:

180 - 155 = 35

Then add this and the known angle:

35 + 60 = 95

Then subtract this from 180 to get the missing angle for x:

180 - 95 = 85

0.02

step-by-step explanation:

time of 9 192 631 770 periods of the radiation corresponding to the transition between the 2 hyperfine levels of the ground state of the caesium 133 atom at 0 k (but other seconds are sometimes used in astronomy)