Tax= sales price x tax percent
Tax= $40 x 6.5%
Convert % decimal to decimal: 6.5% by 100
Tax= 40 x 0.065
Tax= $2.60
Answer: sales tax is $2.60
Hope this helps!
Answer:
D.was Abel to kill all 3 types of bacteria
The technique to improve internal validity is D) Addition of a control group.
<h3>What is
internal validity?</h3>
Internal validity serves as the study which bring about the establishment of a trustworthy cause-and-effect relationship that can be found in treatment and an outcome.
it should be noted that Internal validity also helps to eliminate alternative explanations , hence, The technique to improve internal validity is D) Addition of a control group.
Learn more about internal validity on:
brainly.com/question/968894
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COMPLETE QUESTOIN:
Which of the following is a technique to improve internal validity ____________?
A) Experimenter expectancy
B) Participant bias
C) Use of a confederate
D) Addition of a control group
B) -4
5b=6a+16
9a=7b-20
b=(6/5)a+(16/5)
9a=7((6/5)a+(16/5))-20
9a=(42/5)a+12/5
(3/5)a=12/5
a=4
5b=6(4)+16
5b=24+16
5b=40
b=8
3(4)-2(8)
12-16=-4
