The last one!!! (sorry I can't do recurring signs on my phone!) hope this helps :)

Formula :
Base²= Hypotenuse² - Perpendicular ²












Remember the a² in formula has nothing to do with the a we have to find. :)
Answer:
μ = 5.068 oz
Step-by-step explanation:
Normal distribution formula to use the table attached
Z = (x - μ)/σ
where μ is mean, σ is standard deviation, Z is on x-axis and x is a desired point.
98% of 6-oz. cups will not overflow means that the area below the curve is equal to 0.49; note that the curve is symmetrical respect zero, so, 98% of the cases relied between the interval (μ - some value) and (μ + some value)].
From table attached, area = 0.49 when Z = 2.33. From data, σ = 0.4 oz and x = 6 oz (maximum capacity of the cup). Isolating x from the formula gives
Z = (x - μ)/σ
2.33 = (6 - μ)/0.4
μ = 6 - 2.33*0.4
μ = 5.068
This means that with a mean of 5 oz and a standard deviation of 0.4 oz, the machine will discharge a maximum of 6 oz in the 98% of the cases.
The ratio between the bigger triangle and the smaller triangle is 1:2, which means the smaller triangle is half the size of the bigger triangle.
You simply need to half all the values of the segments of the bigger triangle to find the values of the segments of the smaller triangle.
8/2 = x; 4 = x
6/2 = y; 3 = y