Help please :( thank u

How do you answer this question? (step by step)

Successful implementation of a new system is based on three independent modules. module 1 works properly with probability 0.96. for modules 2 and 3, these probabilities equal 0.95 and 0.90. compute the probability that at least one of these three modules fails to work properly.

The parabola x= √y-9 opens: a.)up b.)down c.)right d.)left