Can somebody help me with these 3 questions please??!!!

Which of these choices show a pair of equivalent expressions?

If rs 900 amounts to rs 1044 in 4 years, what sum will amount to 1368 in 3 1/2 years at the same rate

Adolphin is swimming with her friend. the dolphin jumps to a height of 4.54.54, point, 5 meters above the surface of the water as her friend swims 9.89.89, point, 8 meters directly below her. what is the position of the dolphin's friend relative to the surface of the water? meters