Hi. can anyone me with these problems

1.) 14 - (-17)
2. a bus makes a stop at 2: 30, letting off 13 people and letting on 3. the bus makes another stop ten minutes later to let off 2 more people. how does the number of people on the bus after the second stop compare to the number of people on the bus before the 2: 30 stop? were there fewer people? or more people?
3.) cate and elena were playing a card game. the stack of cards in the middle had 26 cards in it to begin with. cate added 8 cards to the stack. elena then took 7 cards from the stack. finally, cate took 4 cards from the stack. how many cards were left in the stack