Answer:
A
Step-by-step explanation:
We can write this as Sinx by "flipping" the
.
So we will have: 
From basic trigonometry, we know the value of
of sine is of the angle 
<em>But when is sine negative? </em>Either in 3rd or 4th quadrant. But the answer has to be between 0 and
, <em>so we disregard 4th quadrant.</em>
<em />
<em>To get the angle in 3rd quadrant, we add π to the acute angle of the first quadrant (which is π/4 in our case).</em><u><em> Thus we have:</em></u>

A is the right answer.
Reciprocal
Explanation:
I know what I know and this is one of those things
The value of the number 2.4x10⁻⁴ in the standard notation is 0.00024.
<h3>What are Scientific notations?</h3>
The way through which a very small or a very large number can be written in shorthand. In scientific notations when a number between 1 and 10s is multiplied by a power of 10.
For example, 6,500,000,000,000 can be written as 6.5×10¹².
As the value of the scientific notation is given 2.4x10⁻⁴, therefore, for bringing it in the standard form we need to shift the decimal to the left by four digits. So,

Hence, the value of the number 2.4x10⁻⁴ in the standard notation is 0.00024.
Learn more about Scientific notation:
brainly.com/question/1740231