Which sentence with an introductory phrase is punctuated correctly?

a. If they want to defend their championship, the team must avoid mistakes.

b. If they want to defend their championship the team, must avoid mistakes.

c. If they want to defend their championship; the team must avoid mistakes.

d. If they want, to defend their championship, the team must avoid mistakes.

Without a doubt, the correct answer is:

a. If they want to defend their championship, the team must avoid mistakes.

Explanation:

a subordinating (dependent) clause introducing the main (independent) clause

The average time that it takes for the car to travel the first 0.25m is 2.23 s

The average time that it takes for the car to travel the first 0.25 m is given by:

The average time to travel just between 0.25 m and 0.50 m is 0.90 s

First of all, we need to calculate the time the car takes in each trial to travel between 0.25 m and 0.50 m:

Then, the average time can be calculated as

Given the time taken to travel the second 0.25 m section, the velocity would be 0.28 m/s

The velocity of the car while travelling the second 0.25 m section is equal to the distance covered (0.25 m) divided by the average time (0.90 s):