<h2>a) Average velocity in first 4 seconds is 64 ft/s upward</h2><h2>b) Average velocity in second 4 seconds is 63.5 ft/s downward</h2>
Explanation:
a) Given S(t) = 76 + 128t − 16t²
s(0) = 76 + 128 x 0 − 16 x 0² = 76 ft
s(4) = 76 + 128 x 4 − 16 x 4² = 332 ft
Displacement in 4 seconds = 332 - 76 = 256 ft
Time = 4 - 0 = 4 s
Average velocity in first 4 seconds is 64 ft/s upward
a) Given S(t) = 76 + 128t − 16t²
s(4) = 76 + 128 x 4 − 16 x 4² = 332 ft
s(8) = 76 + 128 x 8 − 16 x 8² = 78 ft
Displacement in 4 seconds = 78 - 332 = -254 ft
Time = 4 - 0 = 4 s
Average velocity in second 4 seconds is 63.5 ft/s downward
Although many characteristics are common<span> throughout the </span>group<span>, the heavier metals such as Ca, Sr, Ba, and Ra are almost as reactive as the </span>Group<span> 1 Alkali Metals. All the </span>elements<span> in </span>Group 2 have two<span> electrons in their valence shells, giving them an oxidation state of +</span><span>2.</span>
The light can definitely change the mystery material. This can occur through a change in temperature or color (option C).
A material is affected by light mainly if the material absorbs the light. Based on the chart, we know this mystery material can absorb two types of light:
Moreover, this phenomenon can lead to two main changes:
- Change in temperature: Light affects materials by increasing their temperature of these. A common example is the way the temperature of an object increases if it is exposed to sunlight.
- Change in color: Some materials react to light by changing their color.
Based on this, the material can change its color or temperature.
Note: This question is incomplete; here is the missing part:
A. Yes, but the mystery material can change in only one way, such as by getting warm, because all the light that a material absorbs will affect that material in the same way.
B. No. The mystery material can’t change because the light is not a physical thing. Light cannot change physical things like the mystery material.
C. Yes and the mystery material can change in one or two different ways, such as by getting warm and/or changing color, because different types of light can cause different changes to a material when they are absorbed.
D. There is no way to know whether the mystery material will change or not.
Learn more about sunlight in: brainly.com/question/1603783
That's efficiency. There's no law that it must be stated in percent.
