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There are n sweets in a bag, 6 orange, rest yellow. H takes two, one after another, and eats them. Probability both are orange is 1/3. Show n^2 - n - 90 = 0.

First, we start with what we do know and this should lead us to the answer with steps inbetween. So the amount of yellow sweets to start is (n-6) but we want to focus on the orange sweets. This question i...

Answered by Nicole F. • Maths tutor

3528 Views

When do you use the imperfect tense in Spanish?

One of the main purposes of the imperfect tense is to show that an action has been repeated over a course of time in the past. It can be used, for example, when you want to express hobbies or habits in th...

Answered by Nayaab B. • Spanish tutor

3204 Views

1 a) What is a pathogen? 1 b) How do white blood cells help to defend the body against pathogens?

1 a) a microorganism that causes infectious disease

1 b) White blood cells:

- Ingest pathogens

- produce antibodies which destroy particular bacteria or viruses

...

Answered by Lauraa B. • Biology tutor

6152 Views

When do I use the subjunctive in Spanish?

There are 2 moods in Spanish: the indicative, and the subjunctive.

The indicative is used for anything that is concrete/ factual. For example: "Max habla español" (Max speaks Spanish). Th...

Answered by Maximillian B. • Spanish tutor

2059 Views

25cm3 of NaOH (2M) were titrated with 1.25M H2SO4. Write down the balanced reaction equation. Calculate the number of moles of NaOH used in the titration and hence deduce the volume of sulfuric acid used in the titration. Give your answer in dm3.

2NaOH + H2SO4 -> 2H2O + Na2SO4. moles = concentration x volume. #moles NaOH = 2M x (25/1000)dm3 = 0.05 mol. The reaction equations shows the ratio of alkali to acid is 2:1. The number of moles of H2SO4...

Answered by Tiffany W. • Chemistry tutor

32770 Views