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:
v_avg = 2.9 cm/s
Explanation:
The average velocity of the object is the sum of the distance of all its trajectories divided the time:
x_all is the total distance traveled by the object. In this case you have that the object traveled in the first trajectory 165cm-15cm = 150cm, and in the second one, 165cm - 25cm = 140cm
Then, x_all = 150cm + 140cm = 290cm
The average velocity is, for t = 100s
hence, the average velocity of the object in the total trajectory traveled is 2.9 cm/s
1. stone
s=9,5m
a=g≈10m/s²
t1=?
s=(at²)/2
2s=at²
2s/a=t²
t=√(2s/a)=√(2*9.5m/10m/s²)=√(1,9s²)≈1,38s
2. sound
s=9,5m
V=343m/s²
t2=?
V=s/t
Vt=s
t=s/V=9,5m/343m/s≈0,03s
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V1+V2=1,38s+0,03s=1,41s
"Non nobis Domine, non nobis, sed Nomini tuo da gloriam."
Regards M.Y.