Can anyone help me :(

Which of the following is the sum of 3 1/6 + 6 3/8?

Atriangle abc has two side lengths of 28 ft. and 24 ft. if angle c is 91°, what's the measurement of angle b?

Sound travels about 750 miles per hour. a) suppose it takes about 1.5 seconds to hear the echo. how far away is the canyon wall, in feet? for this i got 825 ft b) suppose you stand 1,925 feet from the canyon wall and sound the horn. how long will it take to hear the echo? (i'm stuck on this)