Answer:
Final answer is c. 15
Step-by-step explanation:
We need to find about what is the first term in the sequence for which d = -2 and a7 = 3
We will use nth term formula of arithmetic sequence.

we have been given a7 that means 7th term is 3
so plug n=7, d=-2 and a_n=3 into above formula




Hence final answer is c. 15
How much does it cost for one movie
29.) This is simply interpreting the linear function.
The function:
96+2.1x
a.) The 96 is what you start with from the beginning. So, we know Rachel weighed 96 ounces when she was born.
b.) Again, interpretation. The 2.1 is the slope, or the change in the line. So we know that Rachel gains 2.1 ounces each day.
30.) For this one, you just have to plug 9 into the equation for x.
The answer is Internal Validity.
Internal Validity is high in an experiment. when it demonstrates persuasively that changes in behavior are caused by the independent variable and not by unknown factors.
What is Internal Validity?
- Internal validity is defined as the degree to which the observed results represent the truth in the population under investigation and are not the consequence of methodological flaws.
- Internal validity is the degree of certainty that the causal link being examined is reliable and unaffected by other factors or variables.
- The extent to which study results may be extended (generalized) to other contexts, groups, or events is referred to as external validity.
To learn more about Internal Validity visit:
brainly.com/question/9292757
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