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How do you know whether to use the preterite tense or the imperfect tense?

That is a very good question, as both describe actions of the past. We use the preterite tense when we talk about actions which are seen as being completed in the past, notably one-off events. For example, y...
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Answered by Zoe S. • Spanish tutor
2842 Views

Make s the subject of the equation: 4st + 8 = 5r

To begin this question, we want to isolate the term containing the s, i.e. have the term containing the s by itself on one side of the equality. We do this by subtracting 8 from both sides. 4st = 5r - 8 To m...
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Answered by Sophie W. • Maths tutor
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A rectangle has an area of 20cm^2. Its length and width are each enlarged by scale factor 3. What is the area of the enlarged rectangle?

For questions regarding enlargements of shapes, it's sometimes easier to consider one dimension at a time. So for this example, let's first consider what the area of the rectangle would be if we just enlarge...
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Answered by Sophie W. • Maths tutor
10080 Views

The points A and B have coordinates (2,4,1) and (3,2,-1) respectively. The point C is such that OC = 2OB, where O is the origin. Find the distance between A and C.

To find the distance between the points A and C, we want to find the magnitude of the vector AC. In order to do this, we must first find the vector AC, which we do by using their position vectors. We are giv...
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Answered by Sophie W. • Maths tutor
12048 Views

How do bacteria become resistant to antibiotics?

That’s a really good question. Well are you familiar with the concept of Natural Selection? (assume correct explanation from the student). Yes, you’re right. It is in fact by this same mechanism that bacteri...
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Answered by Harry C. • Biology tutor
3682 Views