The measure of angle theta is 30 degrees.
This is a 30-60-90 triangle where the short leg is half that of the hypotenuse. The short leg is opposite the smallest angle 30 degrees.
You can use trig to find that
sin(angle) = opposite/hypotenuse
sin(theta) = 5/10
sin(theta) = 0.5
theta = arcsin(0.5)
theta = 30 degrees
C. 20x = 200 because an equation always has an equal sign and other three are expressions because it doesn't have any signs, hoped this helped:)
The string would have to be 4 feet long to have a frequency of 400cps because each foot=100cps
