A river that is popular with kayakers drops more than 770 feet over a stretch of 3.24 miles. The followingelevations were estimated at various distances downriver from the start of the kayaking route by readinga contour map.

(sin 42)/31. = sinx)/37

sinx = 37 (sin42)/31

= 37× 0.66/31 = 0.787

x= 51.9

other angle opposite to y = 180-51.9-42

= 180- 93.9 =86.1

so

sin42)/31 = sin 86.1)/y

0.021 = 0.997 /y

y= 0.997/0.021 =47.47

2nd one in the first row is correct

just sum

10 + 10 = 20