Comparing linear functions word problem

Compare features of two real-world relationships that can be modeled by linear functions, where the functions are represented in different ways.

Problem

Two submersibles, one red and one blue, started rising toward the surface at the same time. They each rose at a constant speed.
The red submersible started rising from an altitude of 80 meters below the surface. After 30 seconds, it was 60 meters below the surface.
The altitude (in meters relative to the surface) of the blue submersible as a function of time (in seconds) is given by the following function:
space, A, left parenthesis, t, right parenthesis, equals, minus, 90, plus, 0, point, 6, t
Which submersible started rising from a higher altitude?
Please choose from one of the following options.
Which submersible rose faster?
Please choose from one of the following options.
Get 3 answers correct in a row