A 4.0-ω resistor, an 8.0-ω resistor, and a 10.0-ω resistor are connected in series across an 11-V battery. The total potential difference across the 4.0-ω and 8.0-ω resistors is:

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination. at the turning point, how far is the second student from the destination?