The hypotenuse of a right triangle measures 10 inches, and the side opposite to ∠θ, one of the non-right angles, is 5 inches long. the measure of ∠θ is

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

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post