1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
SVETLANKA909090 [29]
3 years ago
13

Given the hypothesis that the element zinc prevents cancer, which of the following procedures BEST exemplifies the nature of sci

entific investigation?
A- Analyze zinc, looking for different forms

B- Do research on zinc and its uses throughout history to determine if there is evidence that zinc prevents incidence of cancer


C- Rely on testimony of friends and relatives, as well as conduct a survey to see if there is a concentration of cancer in the people not taking zinc supplements


D- Give zinc supplements to a group of rats and not to another group. After a period of time, determine if there is a higher incidence of cancer in the control group​
Physics
1 answer:
lidiya [134]3 years ago
4 0

Answer:D

Explanation: i found the answer in an answer key!

You might be interested in
What factors affect potential energy
jok3333 [9.3K]
Mass ,gravity and height
6 0
3 years ago
Read 2 more answers
A circuit element consists of a resistor with value 20Ω and inductor with value 10mH connected in series. A voltage of LaTeX: v(
Flura [38]

Answer:

8.97 Watt

Explanation:

Resistance, R = 20 ohm

Inductance, L = 10 mH

V(t) = 20 Cos (1000 t + 45°)

Compare with the standard equation

V(t) = Vo Cos(ωt + Ф)

Ф = 45°

ω = 1000 rad/s

Vo = 20 V

Inductive reactance, XL = ωL = 1000 x 0.01 = 10 ohm

impedance is Z.

Z = \sqrt{R^{2}+X_{L}^{2}}

Z = \sqrt{20^{2}+10^{2}}

Z = 22.36 ohm

V_{rms}=\frac{V_{0}}{\sqrt{2}}

V_{rms}=\frac{20}{\sqrt{2}} = 14.144 V

I_{rms}=\frac{V_{rms}}{Z}=\frac{14.144}{\sqrt{22.36}}=0.634 A

Apparent power is given by

P = Vrms x Irms

P = 14.144 x 0.634

P = 8.97 Watt

6 0
3 years ago
Yall have helped a lot i just need help on this then ill be done for a while
Lubov Fominskaja [6]

Answer:

f(x)=a(x - h)2 + k

Much like a linear function, k works like b in the slope-intercept formula. Like where add or subtract b would determine where the line crosses, in the linear, k determines the vertex of the parabola. If you're going to go up 2, then you need to add 2.

The h determines the movement horizontally. what you put in h determines if it moves left or right. To adjust this, you need to find the number to make the parentheses equal 0 when x equals -2 (because moving the vertex point to the left means subtraction/negatives):

x - h = 0

-2 - h = 0

-h = 2

h = -2

So the function ends up looking like:

f(x)=a(x - (-2))2 + 2

Subtracting a negative cancels the signs out to make a positive:

f(x)=a(x + 2)2 + 2Explanation:

6 0
3 years ago
two clear, colorless liquids are poured together. A bright yellow solid forms. What physical properties have changed?
jek_recluse [69]
Change in state(from liquid to solid) and change in colour I believe.
3 0
3 years ago
What is the difference between professional and casual communication styles?
Lady bird [3.3K]

Answer:

professional communication style is expected to be formal while the casual is informal.

Explanation:

7 0
3 years ago
Other questions:
  • Stan and Silvia Waterson go on a vacation and leave their 17 year old daughter, Jessie, in charge of the house and her two young
    5·1 answer
  • What is the force acting on the object?(g=10m/s^2)​
    10·1 answer
  • A car cruises at a constant rate of 50 miles per hour. How much time will it take to go 600 miles?
    8·1 answer
  • A fly with a mass of 0.0025 kg flies at a rate of 20.0 m/s. What is the kinetic energy of the fly?
    14·2 answers
  • A 200 kg weather rocket is loaded with 100 kg of fuel and fired straight up. It accelerates upward at 30 m/s2 for 30 s, then run
    10·1 answer
  • 1/12 of 1/3 is what fraction?
    8·1 answer
  • If you and your friend EACH apply 55N of force pushing against a wall for 10 minutes. How much work
    7·1 answer
  • Questlon 7 of 10
    9·2 answers
  • Select the correct answer.
    12·1 answer
  • In 1656, the Burgmeister (mayor) of the town of Magdeburg, Germany, Otto Von Guericke, carried out a dramatic demonstration of t
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!