Every seventh time a rat presses a lever, it receives food pallets.
Their research was about the nature of human sexual response and the diagnosis and treatment of sexual disorders and dysfunctions. (Research started in 1957and ended in the 1990’s)
I would say the answer is C. but I’m not 100% sure
<u>This question is off-topic, but I'm answering it assuming you meant to categorize as maths.</u>
Answer:
or 
Explanation:
<u>Factoring</u>
It consists of converting an algebraic expression, usually as a polynomial into two or more factored terms.
We must find the greatest possible common factor and use it to modify the original expression.
The given expression is

It's evident that both terms have a numeric common factor of -9. Let's factor by -9. We must divide each term by -9 to get:

We can even factor further by writing

<span>Warming up is essential to improve mobility in your hips and improve overall performance. When muscles and tendons aren’t warmed up, they don’t work as well. This can increase the chances of you getting a strain or partial tear.
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