Answer:
D
Explanation:
The transcontinental railroad was worked on from both sides of America. At the Pacific Ocean and the Atlantic Ocean. The purpose was to make travel easier from one side of the country to the other, and to get American items to the east and west of America for export to other countries, as well as a few other reasons such as building up the interior of America.
Use the equation:
v = u + at
because it has all the variables given and need to find. First you must make sure units are the same. Acceleration is given in m/s^2. Check to make sure this is correct before using the following solution. Convert acceleration from meters per second squared to miles per hour squared.
look up conversion meters to miles
1 mile = 1609.34 meters
10.60 m/s^2 * 1mile/1609.34m = 0.0069 mi/s^2
there are 3600 seconds in an hour, then there are 3600s*3600s in 1 hr^2
0.0069 mi/s^2 * 3600s*3600s/hr^2 = 85362 mi/hr^2
Then using: v = u +at
60 = 55 + 85362t
60 - 55 = 85362t
5 = 85362t
5/85362 = t
5.9 x 10^-5 hr = t
very small value in hours, multiply by 3600 to convert to seconds.
5.9 x 10^-5 hr * 3600s/hr = 0.21 seconds
After one half-life, 8 g of radioactive isotope will remain in the sample.
<h3>What is radioactivity?</h3>
The act of producing radiation spontaneously is known as radioactivity. This is accomplished by an unstable atomic nucleus that want to give up some energy in order to move to a more stable form.
The following formula is used to compute the number of half lives elapsed:
Hence,8 gram of radioactive isotope remains in the sample after 1 half-life.
To learn more about the radioactivity, refer to the link;
brainly.com/question/1770619
#SPJ1
Answer:
Elements in a period have wide range of chemical properties.
Explanation:
- Period is the row of chemical elements's arrangement in the periodic table. It is numbered from 1 to 7.
- In period as we move towards right the atomic number of element constantly increases along with the change in chemical properties.
- As we move from left towards right in period, the valence electron number regularly increases in every element.
- This valence electron differs the reactivity of the elements.
The Answer is B because primary consumers need to get their food from plants.
