can you please check my work.
A scientist uses a submarine to study ocean life.
She begins at sea level, which is at an elevation of 0 ft.
she travels straight down at a speed of 3.5ft per second.
she then travels directly up 30seconds at a speed of 2.2ft per second.
1) after 120 seconds, what is the scientist's elevation?
I multiplied 90x3.5=315 ft, then I mult. 30x2.2=66
then I subtracted 315-66=249ft down.
2)If the submarine travels at a maximum speed of 5 feet per second, how long would it take to return to sea level? round to the nearest second.
I took the answer from the first part 249 ft and divided it by 5 = 49.8 so I made it 50 seconds.
Are these correct? Thanks for looking over my work.