Respuesta :
sea level is 0...anything below sea level is negative...so that 1312 becomes -1312.
now we subtract...
29028 - (- 1312) =
29028 + 1312 = 30340 ft is the difference
now we subtract...
29028 - (- 1312) =
29028 + 1312 = 30340 ft is the difference