几道英文数学题请教 急

题目

几道英文数学题请教 急
请帮我写出公式
1. a spacecraft countdown is at -8second.in how many seconds will the spacecraft be 15second into its flight.
2. the melvilles sell records at a flea market every saturday.on 4 saturday in june,they had a profit of$30,lost$20,lost$40,and had a profit of $60.how much was their profit or loss in june

答案

1.15-(-8)=23s
2.30-20-40+60=30
So their profit in June is $30