answer: focus or hypocenter
enplanation: when energy release at the focus, seismic waves travel outward from that point in all directions.

As long as the equation in question can be expressed as the sum of the three equations with known enthalpy change, its
can be determined with the Hess's Law. The key is to find the appropriate coefficient for each of the given equations.
Let the three equations with
given be denoted as (1), (2), (3), and the last equation (4). Let
,
, and
be letters such that
. This relationship shall hold for all chemicals involved.
There are three unknowns; it would thus take at least three equations to find their values. Species present on both sides of the equation would cancel out. Thus, let coefficients on the reactant side be positive and those on the product side be negative, such that duplicates would cancel out arithmetically. For instance,
shall resemble the number of
left on the product side when the second equation is directly added to the third. Similarly
Thus
and

Verify this conclusion against a fourth species involved-
for instance. Nitrogen isn't present in the net equation. The sum of its coefficient shall, therefore, be zero.

Apply the Hess's Law based on the coefficients to find the enthalpy change of the last equation.

Answer:
It's C, direct and peripheral.
Explanation:
Just took the test
Inclined planes reduce the amount of effort needed to move an object, but increases the length of the ramp.
<u>Explanation:</u>
Mechanical advantage is the measure of amount of effort needed to move an object. The mechanical advantage can be calculated as the ratio of length of ramp to the height of ramp for an inclined plane.
As it is known that an object can be easily moved on an inclined plane than on a vertical plane, this is because, the inclined plane provides greater output force. But in that case, the effort required will be reduced with the cost of increasing the distance of the movement of object.
In other terms , the ramp's length of inclined planes has to get increased in order to reduce the amount of effort needed to move an object. This is because as the mechanical advantage has length of the ramp in the numerator, with the increase in numerator value or length value the mechanical advantage will also increase.