# 10.5 Homework  (Page 6/7)

 Page 6 / 7

## Try these multiple choice questions.

A new AIDS prevention drugs was tried on a group of 224 HIV positive patients. Forty-five (45) patients developed AIDS after four years. In a control group of 224 HIV positive patients, 68 developed AIDS after four years. We want to test whether the method of treatment reduces the proportion of patients that develop AIDS after four years or if the proportions of the treated group and the untreated group stay the same.

Let the subscript $t$ = treated patient and $\text{ut}$ = untreated patient.

The appropriate hypotheses are:

• ${H}_{o}:{p}_{t}<{p}_{\text{ut}}$ and ${H}_{a}:{p}_{t}\ge {p}_{\text{ut}}$
• ${H}_{o}:{p}_{t}\le {p}_{\text{ut}}$ and ${H}_{a}:{p}_{t}>{p}_{\text{ut}}$
• ${H}_{o}:{p}_{t}={p}_{\text{ut}}$ and ${H}_{a}:{p}_{t}\ne {p}_{\text{ut}}$
• ${H}_{o}:{p}_{t}={p}_{\text{ut}}$ and ${H}_{a}:{p}_{t}<{p}_{\text{ut}}$

D

If the $p$ -value is 0.0062 what is the conclusion (use $\alpha =0.05\text{}$ )?

• The method has no effect.
• There is sufficient evidence to conclude that the method reduces the proportion of HIV positive patients that develop AIDS after four years.
• There is sufficient evidence to conclude that the method increases the proportion of HIV positive patients that develop AIDS after four years.
• There is insufficient evidence to conclude that the method reduces the proportion of HIV positive patients that develop AIDS after four years.

B

Lesley E. Tan investigated the relationship between left-handedness and right-handedness and motor competence in preschool children. Random samples of 41 left-handers and 41 right-handers were given several tests of motor skills to determine if there is evidence of a difference between the children based on this experiment. The experiment produced the means and standard deviations shown below. Determine the appropriate test and best distribution to use for that test.

 Left-handed Right-handed Sample size 41 41 Sample mean 97.5 98.1 Sample standard deviation 17.5 19.2

• Two independent means, normal distribution
• Two independent means, student's-t distribution
• Matched or paired samples, student's-t distribution
• Two population proportions, normal distribution

B

An experiment is conducted to show that blood pressure can be consciously reduced in people trained in a “biofeedback exercise program.” Six (6) subjects were randomly selected and the blood pressure measurements were recorded before and after the training. The difference between blood pressures was calculated $\left(\text{after}-\text{before}\right)$ producing the following results: ${\overline{x}}_{d}=-\text{10}\text{.}2$ ${s}_{d}=8\text{.}4$ . Using the data, test the hypothesis that the blood pressure has decreased after the training,

The distribution for the test is

• ${t}_{5}$
• ${t}_{6}$
• $N\left(-\text{10}\text{.}2,8\text{.}4\right)$
• $N\left(-\text{10}\text{.}2,\frac{8\text{.}4}{\sqrt{6}}\right)$

A

If $\alpha =0\text{.}\text{05}$ , the $p$ -value and the conclusion are

• 0.0014; There is sufficient evidence to conclude that the blood pressure decreased after the training
• 0.0014; There is sufficient evidence to conclude that the blood pressure increased after the training
• 0.0155; There is sufficient evidence to conclude that the blood pressure decreased after the training
• 0.0155; There is sufficient evidence to conclude that the blood pressure increased after the training

C

Is there any normative that regulates the use of silver nanoparticles?
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
why we need to study biomolecules, molecular biology in nanotechnology?
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
why?
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
what does nano mean?
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
it is a goid question and i want to know the answer as well
Maciej
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
for screen printed electrodes ?
SUYASH
What is lattice structure?
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
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