The expression (-2 - 6i)-(-2-4i) to a + bi form is 0 - 2i.
Complete question.
Simplify the expression to a + bi form:
(-2 - 6i)-(-2-4i)
Square root of any negative number are expressed as a complex number. For example i = √-1
Complex numbers are generally written in the format z = x+iy
Given the expression (-2 - 6i)-(-2-4i)), in expansion:
(-2 - 6i)-(-2-4i)
= -2 - 6i + 2+4i
Collect the like terms
= (-2 + 2) - 6i + 4i
= 0 - 2i
Therefore the expression (-2 - 6i)-(-2-4i) to a + bi form is 0 - 2i.
Learn more on complex number here: brainly.com/question/12375854
The recursive definition for the amount of the blood pressure medicine in hareem bloodstream after n hours would be 
Hence, option B is correct.
<h3>What is the recursive rule?</h3>
A rule is defined such that its definition includes itself.
Example:
F(x) = F(x-1) + c
is one such recursive rule.
Hareem takes medicine to control his blood pressure.
he takes a 25 mg pill in the morning.
Suppose that 60% of the medicine is processed by hareem's body by the time he takes a second 25 mg pill in the evening.
So, the recursive definition for the amount of the blood pressure medicine in hareem bloodstream after n hours would be;

Hence, option B is correct.
Learn more about the recursive rule here:
brainly.com/question/12620593
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Answer:
likely, impossible, unlikely
Step-by-step explanation:
Answer:
16 lawns
Step-by-step explanation:
set up a proportion:
(4/5 ÷ 1) = (x÷20)
cross-multiply:
5x = 80
x = 16