D 28 miles you want to multiply by 4 so 7x4 =28
Answer:

Step-by-step explanation:
We have given the equation y = 6 sin (x)
On differentiating both side 
As it passes through the point 
So 
Now the unit vector is parallel to the tangent so m will be 5.196
This passes through the point 
So unit vector will be 

Answer:
420.72
Step-by-step explanation:
1x + 4y = 11 ⇒ 5x + 20y = 55
5x - 7y = -10 ⇒ <u>5x - 7y = -10</u>
<u>27y</u> = <u>65</u>
27 27
y = 2¹¹/₂₇
x + 4(2¹¹/₂₇) = 11
x + 8²²/₂₇ = 11
<u> - 8²²/₂₇ - 8²²/₂₇
</u> x = 2⁵/₂₇
(x, y) = (2⁵/₂₇, 2¹¹/₂₇)