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When do you use the perfect tense as opposed to the imperfect tense?

In general, the imperfect tense is used to describe uncompleted actions whereas the perfect tense is applied when an action is complete. The imperfect explains what happened with no reference to specific tim...
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Answered by Phoebe M. • French tutor
2524 Views

Describe the difference between the function of an effector and receptor, giving an example of each.

Receptors are specialised cells used to detect, stimuli or even convert stimulus in to an impulse. They are usually found in sense organs like the eye, which has light sensitive receptors known as retina, it...
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Answered by Hadijat L. • Biology tutor
9458 Views

Differentiate sin(x)cos(x)

let sin(x)=u , let cos(x)=v du/dx = cos(x), dv/dx = -sin(x) d[sin(x)cos(x)]/dx = v.du/dx + u.dv/dx = cos^2(x) - sin^2(x)
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Answered by James D. • Maths tutor
5411 Views

A box is pulled with a rope at 26° to the horizontal and a tension of 120N. What is the work done in pulling it 5 metres?

Work done = Force in direction of motion (horizontal in this case) x distance. Force in direction of motion is 120 x cos(26) (draw a diagram to help visualise this) and distance is 5. Therefore work done is ...
AR
Answered by Alice R. • Physics tutor
5452 Views

The probability a student in a school wears glasses is 3/7. There are 164 students who DON'T wear glasses. Find the number that wear glasses.

The probability they wear glasses is 3/7, which means the probability they don't is 1-3/7=4/7. This means 164 students make up 4/7 of the school. To find the number that wear glasses we need to find how many...
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Answered by Alice R. • Maths tutor
6763 Views