Answer:
4. (d, the last one)
5. (a, the first one)
Step-by-step explanation:
Answer:
The tank will empty in 4 hours.
Step-by-step explanation:
Since a barrel contains 56 liters of kerosene, and it has two taps, one tap that draws 500 ml every 6 minutes and after first 5 liters are drawn from the barrel, the second tap also starts, and it draws 1 liter in every 5 minutes, to determine how many hours will be taken in all to empty the tank, the following calculation must be performed:
0.5 x X = 5
X = 5 / 0.5
X = 10
10 x 6 = 60
1 hour = 51 liters
1 hour 30 minutes = 51 - (1 x 6) - (0.5 x 5) = 42.5
2 hours = 42.5 - (1 x 6) - (0.5 x 5) = 34
2 hours 30 minutes = 34 - (1 x 6) - (0.5 x 5) = 25.5
3 hours = 25.5 - (1 x 6) - (0.5 x 5) = 17
3 hours 30 minutes = 17 - (1 x 6) - (0.5 x 5) = 8.5
4 hours = 8.5 - (1 x 6) - (0.5 x 5) = 0
Therefore, the tank will empty in 4 hours.
Given:
Consider the expression is

To find:
The value of given expression using a suitable identity.
Solution:
We have,

Using the identity
, we get



Therefore, the value of the given expression is
.
Answer:
B
Step-by-step explanation:
it's basically 2+7
Answer:
(a)
- Independent Variable- Dosage of Omega-3 Fatty Acids
- Dependent Variable - Number of news item remembered
(b)Discrete
(c)Ratio Scale and Discrete Variable
(d) Experimental Method
Step-by-step explanation:
The psychologist wants to evaluate the claim that omega-3 fatty acids can help improve memory in normal adult humans.
(a)In the study, the participants in the two groups were given fish extracts containing Omega-3 (500 mg) and no Omega-3 (0 mg).
The memory test involves measuring the number of items each participant remembers from the past three weeks of news.
Therefore:
- Independent Variable- Dosage of Omega-3
- Dependent Variable - Number of news item remembered
(b) The dependent variable is discrete since the number of news items remembered can only be whole numbers.
(c)The independent variable is in milligrams of Omega-3 where the placebo is 0 mg. This is a ratio scale since it has an absolute zero.
Since the dosage is given in multiples of 50mg, it is a discrete variable.
(d)Since the psychologist seeks to manipulate the conditions of the study by introducing Omega-3 to some of the participants and placebo to other participants, it is an experimental distribution.