Number 19 is frequency and not sure which question you asked!!!??
Answer:
a).
Wmin= 2471.03 J
W=1603.01 J
Explanation:
Weight, w= 2267 N

Minimum work 'h' is the distance the refrigerator is raised h=1.09m

The motion is no frictional force so, the magnitude of the force with a angle of 45.0° is find using:

A centimeter cannot measure mass because mass is measured by grams.
Answer: Centimeter
Answer:
The first flowering plants appeared in the Mesozoic era, not the Paleozoic era
Explanation:
The Mesozoic era is well known and most famous because of the rule of the dinosaurs which were the dominant animals for most of this are. Also, it is the era in which the mammals appeared, though they lived in the shadows of the dinosaurs and only became dominant after their extinction. Another important evolution that took place and is not mentioned very often is the appearance of the first flowering plants. This was a revolutionary trait for the plants, and it helped them to survive in the changing climate on Earth. Soon this trait enabled this type of plants to spread out significantly and to become one of the most dominant organisms on the planet in the following era.
Answer:
<h2>66.67 km/hr</h2>
Explanation:
The average velocity of the car can be found by using the formula

d is the distance
t is the time taken
From the question we have

We have the final answer as
<h3>66.67 km/hr</h3>
Hope this helps you