Question

CRITICAL THINKING 5. Resolution of rigor mortis starts three days after death, the possible reason is? A. Lactic acid fermentation B. Decreased temperature C. Release of phosphor-creatin D. Decomposition​

Answer 1

Given :- A certain star is 4.3×10² light years from Earth. One light year is about 5.9×10¹² miles.

To Find :- How far from Earth (in miles) is the star?

Solution :-

We are given the following:

1 light year = 5.9 x 10¹² miles

Distance of the star = 4.3 x 10² light years

To get this we just convert the distance of the star in light years into miles.

$4.3 \: \times {10}^{2} lightyears \: \times \frac{5.9 \times {10}^{12} miles}{1 \: lightyear}$

$= (4.3 \times {10}^{2} ) \times (5.9 \times {10}^{12} miles)$

In dealing with scientific notation, when we multiply them we can treat the coefficients and exponents of 10 separately.

Coefficients:

4.3 x 5.9 = 25.37

Exponents of 10:

10² x 10¹² = 10⁽²⁺¹²⁾=10¹⁴

Then we combine them again to form a scientific notation:

25.37 x 10¹⁴

But since the standard in writing a scientific notation, the coefficient needs to be a number from 1-9, we need to move the decimal. When we move the decimal to the right or left, we change the exponent of the power of 10. Since we will move it once to the left, we add 1.

Hence, 25.37 × 10¹⁴ = 2.537 × 10¹⁵

Hence, the star is 2.537 × 10¹⁵ miles far from the Earth.

Hence, the final answer is 2.537 × 10¹⁵ miles.