22. Julie took a road trip to Canada. She traveled a total of 1,750 miles in 25 hours. Calculate Julie's average speed.

s = 70 m/h

Explanation:

Given data:

Distance traveled = 1750 mile

Time taken = 25 hours

Average speed = ?

Solution:

Average speed can be calculated by dividing distance traveled over time taken.

Formula:

s = d/t

by putting values,

s = 1750 mile / 25 hour

s = 70 m/h

At the end of second half life 12.5 g will left

Explanation:

Given data:

Total Mass = 50 g

Half lives = 2

Mass remain at the end = ?

Solution:

At time zero = 50 g

At 1st half life = 50 g /2 = 25 g

At second half life = 25 g/2 = 12.5 g

So at the end of second half life 12.5 g will left.