From that ragged, motley list of statements, only 'C' is true.
The mass is 10.811 hope this helps
Answer:
The force of friction acting on block B is approximately 26.7N. Note: this result does not match any value from your multiple choice list. Please see comment at the end of this answer.
Explanation:
The acting force F=75N pushes block A into acceleration to the left. Through a kinetic friction force, block B also accelerates to the left, however, the maximum of the friction force (which is unknown) makes block B accelerate by 0.5 m/s^2 slower than the block A, hence appearing it to accelerate with 0.5 m/s^2 to the right relative to the block A.
To solve this problem, start with setting up the net force equations for both block A and B:

where forces acting to the left are positive and those acting to the right are negative. The friction force F_fr in the first equation is due to A acting on B and in the second equation due to B acting on A. They are opposite in direction but have the same magnitude (Newton's third law). We also know that B accelerates 0.5 slower than A:

Now we can solve the system of 3 equations for a_A, a_B and finally for F_fr:

The force of friction acting on block B is approximately 26.7N.
This answer has been verified by multiple people and is correct for the provided values in your question. I recommend double-checking the text of your question for any typos and letting us know in the comments section.
Answer;
-Sensors
-Sensors are placed on dangerous machinery to detect motion, light, heat, pressure, or another stimulus. Their presence helps protect operators from injury while working on machines.
Explanation;
-Machinery, safety and factory floor sensors and switches help workers become more productive, efficient, and safe.
-Hazardous machines and systems are frequently equipped with safety elements (safety doors) with a locking mechanism to protect the operator. Their function is to prevent hazardous machine functions if the safety door is not closed and locked and to keep the safety door closed and locked until the risk of injury has passed.
The average thickness of a sheet of the paper is 0.1 mm.
The number of ice blocks that can be stored in the freezer is 80 blocks of ice.
<h3>Average thickness of a sheet of the paper</h3>
The average thickness of a sheet of the paper is calculated as follows;
average thickness = 6 mm/60 sheets = 0.1 mm /sheet
Thus, the average thickness of a sheet of the paper is 0.1 mm.
<h3>Volume of each block of ice</h3>
Volume = 10 cm x 10 cm x 4 cm
Volume = 400 cm³
<h3>Volume of the freezer</h3>
Volume = 40 cm x 40 cm x 20 cm = 32,000 cm³
<h3>Number of ice blocks that can be stored</h3>
n = 32,000 cm³/400 cm³
n = 80 blocks of ice
Thus, the number of ice blocks that can be stored in the freezer is 80 blocks of ice.
Learn more about average thickness here: brainly.com/question/24268651
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