There are 100 centimeters in 1 meter. So to start with you must multiply 10000 by 100 to determine the number of centimeters in each race. This answer will be 1000000. Then to determine the number of centimeters in fifty races, you must multiply 1000000 by 50. This answer is 50000000. Then you must put it in scientific notation.
To do this you must move the decimal place over to the left until there is only one, nonzero number in front of it. Because you will move it to the left, your exponent will be positive. Therefore, your answer will be B.
This is the standard form equation 
What is the ellipse?
The equation for an ellipse is typically written as x² a² + y² b² = 1. x² a² + y² b² = 1. An ellipse with its origin at the center is defined by this equation. The ellipse is stretched further in both the horizontal and vertical directions if a > b, a > b, and if b > a, b > a, respectively.
The standard form of the equation of an ellipse with center (h, k)and major axis parallel to the x-axis is:

where,
a > b
the length of the major axis is 2a
the coordinates of the vertices are (h±a,k)
the length of the minor axis is 2b
the coordinates of the co-vertices are (h,k±b)
the coordinates of the foci are (h±c,k),
where c² = a² − b².
so,

Hence, this is the standard form equation
.
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Answer:

Step-by-step explanation:

Answer:
-7.5x3+(20+2.5)=0
this one is equal to 0 ;)
<span>C. 5x – 1 im possitive</span>