For a standard normal distribution, which of the following expressions must always be equal to 1?
a) p(z≤-a)-p(-a≤z≤a)+p(z≥a)
b) p(z≤-a)-p(-a≤z≤a)+p(z≥a)
c) p(z≤-a)+p(-a≤z≤a)-p(z≥a)
d) p(z≤-a)+p(-a≤z≤a)+p(z≥a)

answer rather than having to add and subtract the measurements of the semi-circle, notice that the semicircle to the left of ad is actually identical in area to the blank semicircle-shaped space to the left of bc. so if we transferred the red semicircle into the blank space, we would end up with a square of side length 24 cm. the area of a square is s^2 = 24^2 = 676 cm^2.

u also answered this so i think u would know but i am here to

put in or use mine