Alpha (a) is used to measure the error for decisions concerning true null hypotheses. What is beta (ß) error used to measure?

Alpha (α) is used to measure the error for decisions concerning true null hypotheses, while beta (ß) is used to measure error for decisions concerning false null hypotheses.

Step-by-step explanation:

Suppose we have events X and Y.

1. If it is said that X equals Y, when X is actually not equal to Y, α is used in this case, the null hypotheses.

2. If X is said to not be equal to Y, when X is actually equal to Y, β is used in this case, the false null hypotheses.

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.