20 percent
If you cross multiply 30 w/ 100 and then divide it by 150 you will get 20.
The Z-score is calculated by the formula below

Step 2: Substitute the given parameters in the formula

Hence, the z-score of a person who scored 145 on the exam is -0.5
Standard for is x × 10 ^I
where,
I = indice
10 > x < 0
you cannot write this is standard form with putting in what they stand for. However you can simplify it -
4(8m-7n) +6(3n-4m)
32m - 28n + 18n - 24m
8m - 10n
but hey I am from England do what we call standard form might be different
If you need it rounded, it would be 2 then 20 then 76.1. If you just need the base numbers, it would be 1 then 19 then 76.7
=(-4/5)^2 * -3/50
square -4/5 first; remember -4/5^2 is the same as -4/5 * -4/5
=(-4/5 * -4/5) * -3/50
multiply -4 numerators; multiply 5 denominators
=(-4 * -4)/(5 * 5) * -3/50
=16/25 * -3/50
multiply numerators 16 & -3; multiply denominators 25 & 50
=(16 * -3)/(25 * 50)
= -48/1250
simplify by 2
= -24/625 (or -0.0384)
ANSWER: -24/625 (or -0.0384)
Hope this helps! :)