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).
It's a chemical change since it cannot be reversed and the saliva releases a new substance
Answer:
Granite
Explanation:
Trust me I learned this 2years ago
The magnitude of the resultant is
√ (22² + 2.2²) = √ (484 + 4.84) = √488.84 = 22.11 m/s .
The direction of the resultant is
tan⁻¹(22N / 2.2E) = tan⁻¹(10) = 5.71° east of north .
Answer: 7200 m
Explanation: The solution is, first convert 15 minutes to seconds.
15 mins x 60 s / 1 min = 900 s
Use the formula for speed which is v= d/t then derive for d.
d = vt
= 8 m/s ( 900s)
= 7200 m
