Answer:
Atomic mass is defined as the number of protons and neutrons in an atom
Index fossils are used to determine the relative ages of rock and fossils and are also used to define the boundaries between geologic periods.
<u>Option: A</u>
<u>Explanation:</u>
The fossils which are recognized as fossils guides or indicator fossils are used to classify and recognize geological or faunal periods, termed as index fossils. It must be of short vertical reach, wide geographic distribution and swift patterns in evolution. It helps to assess the rock layers ' age and helps to date other fossils found close and around them. For an instance, Ammonites were abundant in the Mesozoic period between 245 to 65 mya, they have not been found after the Cretaceous era, as they became endangered during the K-T extinction (65 mya).
<span>Hudson Bay drainage basin</span>
Answer:
The average velocity is 7.5 km/h
Explanation:
Let's convert minutes to hours so our answer can be given in a common units of km/hour:
12 minutes = 12/60 hours = 0.2 hours
Now we estimate the average velocity calculating the distance travelled over the time it took:
1.5 / 0.2 km/h = 7.5 km/h
Answer:
Vy = V0 sin 38 where Vy is the initial vertical velocity
The ball will accelerate downwards (until it lands)
Note the signs involved if Vy is positive then g must be negative
The acceleration is constant until the ball lands
t (upwards) = (0 - Vy) / -g = Vy / g final velocity = 0
t(downwards = (-Vy - 0) / -g = Vy / g final velocity = -Vy
time upwards = time downwards (conservation laws)