John sees Linda running towards him at 11 m/s. While running, Linda throws a ball to John at 5 m/s. What is the speed of the ball as observed by John?

Rohit is trying to tune an instrument

The energy released by a nuclear fusion reaction is produced when

According to valence bond theory, which orbitals overlap in the formation of the bond in hf according to valence bond theory, which orbitals overlap in the formation of the bond in hf 2s on h and 2p on f 1s on h and 2s on f 1s on h and 1p on f 1s on h and 2p on f 1s on h and 3p on f