hello
12.
from a careful observation, one would notice that line VS is the diameter of the circle and ut is the lenght of an arc. however, we have to find the angle UT

note: vs is equal to 180 degrees because angle on a straight line is equal to 180 degree

now we can solve for angle UT easily

now we have the value of angle msince we know the value of angle UT, we can use this information to solve for length of the arc of UT

from the calculations above, the length of the arc UT is equal to 3.87m