Answer:
b. E (about 329 Hz)
Explanation:
Given data:
Initial length of the string l1= 24 in
initial frequency f1= 247 Hz
changed length l2= 18 in
Then we have to find the changed frequency f2= ?
We already now that
frequency f ∝ 1/length of the string l
therefore,

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Answer: The control group is the part where you see what happens when you change a variable you want to study/examine. Basically, you need the control group because you need something to see what happens when you change something.
Hope this Helps! :))))
Answer;
B. both a non-directional and directional hypothesis
Explanation;
A two-tailed test is the standard test of significance to determine if there is a relationship between variables in either direction. Two-tailed tests do this by dividing the .05 in two and putting half on each side of the bell curve.
A non-directional hypothesis is a type of alternative hypothesis used in statistical significance testing. In contrast, a directional alternative hypothesis specifies the direction of the tested relationship, stating that one variable is predicted to be larger or smaller than null value, but not both.
Answer:
In the air
Explanation:
light in air flows in a straight direction while in water it curves far away from the object(refraction)thus the bear in the air will catch the fish easily because in water the fish is refracted thus the bear may catch its refracted image thinking it is the fish
Answer:
<em>A. 751 ohm</em>
Explanation:
Impedance: <em>This is the total opposition to the flow of current in an a.c circuit by any or all of the three circuit elements ( R, L, C). The unit of impedance is Ohms (Ω). The impedance in a parallel circuit is gives a s</em>
<em>Z = RXₐ/√(Xₐ² + R²)............................... Equation 1</em>
<em>Where Z = The impedance of the a.c circuit, Xₐ = capacitive reactance, R = resistance.</em>
<em>Given: Xₐ = 962 Ω, R = 1200 Ω</em>
<em>Substituting these values into equation 1,</em>
<em>Z = 962×1200/√(962² + 1200²)</em>
<em>Z = 1154400/√(925444 + 1440000)</em>
<em>Z = 1154400/√(925444+1440000</em>
<em>Z = 1154400/1538</em>
<em>Z = 750.59 Ω</em>
<em>Z≈ 751 Ω</em>
<em>Therefore the impedance of the circuit = 751 Ω</em>
<em>The right option is A. 751 ohm</em>