Answer:
See Explanation
Step-by-step explanation:
a) Additive inverse of −2
- the additive inverse of a number a is the number that, when added to 'a', yields zero. This number is also known as the opposite (number), sign change, and negation.
- So the Additive inverse of -2 is 2. ∴ -2+2=0
b) Additive identity of −5
- Additive identity is the value when added to a number, results in the original number. When we add 0 to any real number, we get the same real number.
- -5 + 0 = -5. Therefore, 0 is the additive identity of any real number.
c) additive inverse of 3
- Two numbers are additive inverses if they add to give a sum of zero. 3 and -3 are additive inverses since 3 + (-3) = 0. -3 is the additive inverse of 3.
d). multiplicative identity of 19
- an identity element (such as 1 in the group of rational numbers without 0) that in a given mathematical system leaves unchanged any element by which it is multiplied
- Multiplicative identity if 19 is 1 only, since 19 x 1 = 19.
e) multiplicative inverse of 7
- Dividing by a number is equivalent to multiplying by the reciprocal of the number. Thus, 7 ÷7=7 × 1⁄7 =1. Here, 1⁄7 is called the multiplicative inverse of 7.
d) | 11-5|×|1-5|
- | 11-5|×|1-5| ⇒ I6I×I-4I ⇒ 6×4 ⇒ 24
If we want to has 100 in the denominator we have to divide numerator and denominator by 2. Then total value of fraction doesnt change.

Now read the fraction, its 23 hundreds, now just write as decimal, so,
0.23
Markup = $4
b) markup as a percentage of cost is 33.3%
Step-by-step explanation:
Markup
markup = selling price - cost
= $13 - 9
... markup = $3
Markup as a Percentage of Cost
To find the percent markup, divide the markup by the reference value and multiply the ratio by 100%. The reference value for markup is usually cost price, but sometimes may be selling price.
... markup / cost × 100% = 3/9×100% = 33 1/3% ≈ 33.3%