Answer:
7.41
Step-by-step explanation:
Vertical component:
S = 268.8
U = 0
V =?
A = 9.8
T=?
S = ut + 0.5at^2. u = 0
268.8 = 0.5x9. 8xt^2
T = 7.41 seconds
<h3>
Answer: Choice C) Construct a tangent from an external point</h3>
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Explanation:
The idea is that you have some circle and a point outside the circle. This point is labeled M. The center of the circle is point O. A perpendicular bisector is constructed to segment OM, after which a compass is used to draw the arc marking to form point G. Line MG is perpendicular to the radius segment OG. Therefore, line MG is tangent to the circle and it goes through point M.
Answer:

Step-by-step explanation:
Since
and
are complex conjugates, let's define them as follows:



Since
is a real number, complex part of above result must be zero.

From to hold above equality,
or
.
However, since
, 
So,
or 
And since
and
are complex conjugates, taking plus or minus sign as found above will not affect the result, so let's write the last version of
and
as follows:


Since 
⇒ 
Finally,
⇒ 