<span>The answer is C. temperature, light level, species of bacteria. All three variables are considerations regarding the reproduction rate of the bacteria. The other three answer choices can be eliminated easily because they each contain at least one irrelevant variable. In particular, all three contain a variable that makes reference to Jack's personal characteristics. These do not have any impact on the experiment and readily stand out to disqualify the entire answer choice.</span>
Answer:
C
Explanation:
Im not sure but I did somthing simalier
Between centre of curvature and principal focus.
When the resultant force is not equal to zero termed an unbalanced force. By procedures 4 and 5 students observe an unbalanced upward force on Box 1. Hence option 1 is right for the problem.
<h3>What is an unbalanced force?</h3>
The forces operating on a body are known as unbalanced forces when the resulting force exerted on it is not equal to zero.
Unbalanced forces acting on the body, causing it to modify its state of motion. To further grasp the nature of imbalanced forces.
<h3 />
The following reasons by which we can understand the unbalanced force caused by the box.
Due to these two reasons, books will move up.
By adding another mass to box 2. The box becomes lighter. As the box becomes lighter the gravity force acting on the box will be less due to which the box easily can move up.
By removing the two masses from box 1. Due to which other become heavier other becomes heavier pulling it down causing box 1 one to go up.
Hence by procedures 4 and 5 students observe an unbalanced upward force on Box 1. Hence option 1 is right for the problem.
To learn more about the unbalanced force refer to the link;
brainly.com/question/227461
Answer: It is D.
Explanation:
The compass needle pointed in the direction of the current's magnetic field.
