Find the indicated area under the curve of the standard normal distribution; then convert it to a percentage and fill in the blank. About % of the area is between z2 and z2 (or within 2 standard deviations of the mean). About nothing% of the area is between z2 and z2 (or within 2 standard deviations of the mean).

95%

Step-by-step explanation:

About 95% of the area is within two standard deviation in standard normal distribution. This can be explained by finding the probability within 2 standard deviation using standard normal distribution.

P(z1<Z<z2)=P(-2<Z<2)

P(-2<Z<2)=P(-2<Z<0)+P(0<Z<2)

P(-2<Z<2)=0.4772+0.4772

P(-2<Z<2)=0.9544

Thus, About 95% of the area is between z2 and z2

answer:   28.56 feet (approx)

step-by-step explanation:

since, triangle abc has measure of angle c equal to 55 degrees, measure of angle abc equal to 90 degrees, and length of bc equal to 20 feet.

we have to find out the measurement of segment ab.

therefore, tan 55° =

but bc = 20 feet.

⇒ tan 55 ° =  

⇒ ab = 20 × tan 55 °

⇒ ab = 20 × 1.42814800674

⇒ ab = 28.5629601348   ≈ 28.56 feet