If a simple machine requires an effort of 20 newtons to lift a load of 100 newtons, its mechanical advantage is:
a. 5
b. 5N
c. 5MA​

100,000 random people were tested for condition a. roberto's doctor told him he tested positive for condition a. if the test is 99% accurate and condition a is rare—one out of every thousand people have it. what is the probability that testing positive means roberto has condition a? 99.0% 1% 9% 99.9%