Tactics : can you solve these?

These tactics will have you end up at least 2 pawns worth of material up. Choose the best solution, as to each problem has just one best answer. I will periodically post some interesting tactics I come across that I could solve. Can you solve them too? Tactics are a great way to increase the speed, accuracy, and depth of your calculations in games. I suggest you work on them frequently. I would recommend pausing up to even 10 minutes on these tactics if you are not fast at solving chess problems. Taking long amounts of time teaches your brain how to solve complicated positions, and later on the thinking process becomes more automatic.