A submarine is 105 feet below the surface of the water, and it begins to ascend at a rate of 3 feet per minute. After how many minutes will the submarine be 81 feet below the surface?

8 minutes

Step-by-step explanation:

Step one:

given

A submarine is 105 feet below the surface of the water

depth of submarine= 105 feet

let the time of ascending be x

Required

The time taken to ascend up to 81 ft

Step two:

the expression for the situation is

81=105-3x

solve for x

3x=105-81

3x=24

divide both sides by 3

x= 24/3

x=8 minutes

answer: i don't understand. what are the options

step-by-step explanation:

b) 1/3 * 1/5

step-by-step explanation:

each smallest part is 1/15 since the written one is 1/5 and it's divided by 3 equal parts. (1/5 )/3 = 1/15 = 1/3 * 1/5