Pls help me on this ixl assignment i am not good in math

What is the value with a place of tenths in 907.456 1) 0 2) 6 3) 4 4) 5

An architect is designing a water fountain for a park she uses the given function to model the water jet flowing from the fountain nozzles where h(x) gives the height of the water jugs in feet x feet from the starting point h(x)=-1/20x+x+15

Consider 6x2 + 6x + 1. which term immediately tells you that this expression is not a perfect square trinomial? justify your answer