Answer:
0.000298 = 0.0298% probability that the system will collapse
Step-by-step explanation:
Number of possible ways the system can fail:
2 lines from a set of 3 fail, or all three fail.
Two from a set of 3:
Can be A and B, A and C, or B and C. Three possible outcomes then.
The probability of each is:
0.01*0.01*0.99
Two failling, each with 0.01 probability, and 1 working, with 0.99 probability.
All three:
Each with 0.01 probability.
a) What is the probability that the system will collapse
Both cases, so

0.000298 = 0.0298% probability that the system will collapse
30 degrees is what the answer is because it says it in the question
What exactly are you looking for? Do you want the answer to all of them?
First you chang top fractions into decimal add and divide that by 4 which is equal to 0.375 hope it helps.