Answer:
on an average, <em>2</em><em>0</em><em>H</em><em>z</em><em> </em><em>to</em><em> </em><em>2</em><em>0</em><em>k</em><em>H</em><em>z</em>
I believe it’s A. I know for sure it isn’t D.
Answer:

Explanation:
Given data

To find
Magnitude of the net magnetic field B
Solution
The magnitude of the net magnetic field can be find as:

<h2>
Answer: 12 s</h2>
Explanation:
The situation described here is parabolic movement. However, as we are told <u>the instrument is thrown upward</u> from the surface, we will only use the equations related to the Y axis.
In this sense, the main movement equation in the Y axis is:
(1)
Where:
is the instrument's final position
is the instrument's initial position
is the instrument's initial velocity
is the time the parabolic movement lasts
is the acceleration due to gravity at the surface of planet X.
As we know
and
when the object hits the ground, equation (1) is rewritten as:
(2)
Finding
:
(3)
(4)
(5)
Finally:

D. All of the above
At high tide fish will feed among the mangrove roots - rich fishing ground
The trees trap sediment and soil in the river that would flow out to sea which also helps stop erosion
Wildlife utilise almost every part of the tree, with insects and birds, monkeys and lizards in the branches, shrimps and fish in the roots, and snails and clams in the soil